Posts in category 'number-theory'
G.247 unit
An:term:**unit** <unit> is that by virtue of which each of the things that exist is called one.
G.248 number
A:term:**number** <number> is a multitude composed of:term:units <G.247>.
G.249 numbers prime to one another
Numbers prime to one another are those which are:term:measured <G.253> by an:term:unit <G.247> alone as a common measure.
G.250 unequal numbers set
Two unequal numbers being set out, and the less being continually subtracted in turn from the greater, if the number which is left never measures the one before it until an unit is left, the original numbers is prime to one another.
G.251 numbers prime find
Given two numbers not prime to one another, to find their greatest common measure.
G.252 numbers prime find
Given three numbers not prime to one another, to find their greatest common measure.
G.253 part of a number
A:term:number <G.248> is a:term:**part** <part-aliquot> of a number, the less of the greater, when it:term:measures <part-aliquot> the greater;
G.254 parts of a number
But:term:**parts** <parts-non-aliquot> when it does not:term:measure <G.253> it.
G.255 number part parts
Any number is either a part or parts of any number, the less of the greater.
G.256 multiple of a number
The greater:term:number <G.248> is a:term:**multiple** <multiple> of the less when it is:term:measured <G.253> by the less.
G.257 number part number
If a number be a part of a number, and another be the same part of another, the sum is the same part of the sum that the one is of the one.
G.258 number parts number
If a number be parts of a number, and another be the same parts of another, the sum is the same parts of the sum that the one is of the one.
G.259 number part number
If a number be that part of a number, which a number subtracted is of a number subtracted, the remainder is the same part of the remainder that the whole is of the whole.
G.260 number parts number
If a number be the same parts of a number that a number subtracted is of a number subtracted, the remainder is the same parts of the remainder that the whole is of the whole.
G.261 number part number
If a number be a part of a number, and another be the same part of another, alternately also, whatever part or parts the first is of the third, the same part, or the same parts, will the second also be of the fourth.
G.262 number parts number
If a number be parts of a number, and another be the same parts of another, alternately also, whatever parts or part the first is of the third, the same parts or the same part will the second also be of the fourth.
G.263 proportional numbers
Numbers are:term:**proportional** <G.180> when the first is the:term:same multiple <G.256>, or the:term:same part <G.253>, or the:term:same parts <G.254>, of the second that the third is of the fourth.
G.264 whole whole number
If, as whole is to whole, so is a number subtracted to a number subtracted, the remainder is to the remainder as whole to whole.
G.265 there many numbers
If there be as many numbers as we please in proportion, then, as one of the antecedents is to one of the consequents, so are all the antecedents to all the consequents.
G.266 numbers proportional proportional
If four numbers be proportional, they is proportional alternately.
G.267 there many numbers
If there be as many numbers as we please, and others equal to them in multitude, which taken two and two are in the same ratio, they is in the same ratio ex aequali.
G.268 unit measure number
If an unit measure any number, and another number measure any other number the same number of times, alternately also, the unit will measure the third number the same number of times that the second measures the fourth.
G.269 multiplication of numbers
A:term:number <G.248> is said to:term:**multiply** <multiply> a number when that which is multiplied is added to itself as many times as there are:term:units <G.247> in the other, and thus some number is produced.
G.270 numbers multiplying make
If two numbers by multiplying one another make certain numbers, the numbers so produced are equal.
G.271 number multiplying numbers
If a number by multiplying two numbers make certain numbers, the numbers so produced will have the same ratio as the numbers multiplied.
G.272 numbers multiplying number
If two numbers by multiplying any number make certain numbers, the numbers so produced will have the same ratio as the multipliers.
G.273 numbers proportional number
If four numbers be proportional, the number produced from the first and fourth will equals the number produced from the second and third; and, if the number produced from the first and fourth equals that produced from the second and third, the four numbers is proportional.
G.274 least numbers ratio
The least numbers of those which have the same ratio with them measure those which have the same ratio the same number of times, the greater the greater and the less the less.
G.275 numbers prime least
Numbers prime to one another are the least of those which have the same ratio with them.
G.276 least numbers ratio
The least numbers of those which have the same ratio with them are prime to one another.
G.277 numbers prime number
If two numbers be prime to one another, the number which measures the one of them is prime to the remaining number.
G.278 numbers prime number
If two numbers be prime to any number, their product also is prime to the same.
G.279 numbers prime product
If two numbers be prime to one another, the product of one of them into itself is prime to the remaining one.
G.280 numbers prime numbers
If two numbers be prime to two numbers, both to each, their products also is prime to one another.
G.281 numbers prime multiplying
If two numbers be prime to one another, and each by multiplying itself make a certain number, the products is prime to one another; and, if the original numbers by multiplying the products make certain numbers, the latter is prime to one another [and this is always the case with the extremes].
G.282 numbers prime sum
If two numbers be prime to one another, the sum is prime to each of them; and, if the sum of two numbers be prime to any one of them, the original numbers is prime to one another.
G.283 prime number
A:term:**prime number** <prime-number> is that which is:term:measured <G.253> by an:term:unit <G.247> alone.
G.284 prime number prime
Any prime number is prime to any number which it does not measure.
G.285 numbers multiplying make
If two numbers by multiplying one another make some number, and any prime number measure the product, it will also measure one of the original numbers.
G.286 composite number
A:term:**composite number** <composite-number> is that which is:term:measured <G.253> by some:term:number <G.248>.
G.287 composite number measured
Any composite number is measured by some prime number.
G.288 number prime measured
Any number either is prime or is measured by some prime number.
G.289 many numbers please
Given as many numbers as we please, to find the least of those which have the same ratio with them.
G.290 numbers find least
Given two numbers, to find the least number which they measure.
G.291 numbers measure number
If two numbers measure any number, the least number measured by them will also measure the same.
G.292 numbers find least
Given three numbers, to find the least number which they measure.
G.293 number measured number
If a number be measured by any number, the number which is measured will have a part called by the same name as the measuring number.
G.294 number part whatever
If a number have any part whatever, it is measured by a number called by the same name as the part.
G.295 find the number which is the least that
Find the number which is the least that will have given parts.
G.296 there many numbers
If there be as many numbers as we please in continued proportion, and the extremes of them be prime to one another, the numbers are the least of those which have the same ratio with them.
G.297 find numbers in continued proportion
Find numbers in continued proportion, as many as may be prescribed, and the least that are in a given ratio.
G.298 many numbers please
If as many numbers as we please in continued proportion be the least of those which have the same ratio with them, the extremes of them are prime to one another.
G.299 many ratios please
Given as many ratios as we please in least numbers, to find numbers in continued proportion which are the least in the given ratios.
G.300 plane and solid numbers
And, when two:term:numbers <G.248> having:term:multiplied <G.269> one another make some number, the number so produced is called:term:**plane** <plane-number>, and its:term:**sides** <side-of-number> are the numbers which have multiplied one another.
G.301 plane numbers ratio
Plane numbers have to one another the ratio compounded of the ratios of their sides.
G.302 even number
An:term:**even number** <even-number> is that which is divisible into two equal parts.
G.303 there many numbers
If there be as many numbers as we please in continued proportion, and the first do not measure the second, neither will any other measure any other.
G.304 there many numbers
If there be as many numbers as we please in continued proportion, and the first measure the last, it will measure the second also.
G.305 numbers there fall
If between two numbers there fall numbers in continued proportion with them, then, however many numbers fall between them in continued proportion, so many will also fall in continued proportion between the numbers which have the same ratio with the original numbers.
G.306 numbers prime numbers
If two numbers be prime to one another, and numbers fall between them in continued proportion, then, however many numbers fall between them in continued proportion, so many will also fall between each of them and an unit in continued proportion.
G.307 numbers fall numbers
If numbers fall between each of two numbers and an unit in continued proportion, however many numbers fall between each of them and an unit in continued proportion, so many also will fall between the numbers themselves in continued proportion.
G.308 cube number
A:term:**square number** <square-number> is equal:term:multiplied <G.269> by equal, or a:term:number <G.248> which is contained by two equal numbers.
G.309 square numbers there
Between two square numbers there is one mean proportional number, and the square has to the square the ratio duplicate of that which the side has to the side.
G.311 square number
And a:term:**cube** <cube-number> is equal:term:multiplied <G.269> by equal and again by equal, or a:term:number <G.248> which is contained by three equal numbers.
G.312 cube numbers there
Between two cube numbers there are two mean proportional numbers, and the cube has to the cube the ratio triplicate of that which the side has to the side.
G.313 there many numbers
If there be as many numbers as we please in continued proportion, and each by multiplying itself make some number, the products is proportional; and, if the original numbers by multiplying the products make certain numbers, the latter is proportional.
G.314 square measure square
If a square measure a square, the side will also measure the side; and, if the side measure the side, the square will also measure the square.
G.315 cube number measure
If a cube number measure a cube number, the side will also measure the side; and, if the side measure the side, the cube will also measure the cube.
G.316 square number measure
If a square number do not measure a square number, neither will the side measure the side; and, if the side do not measure the side, neither will the square measure the square.
G.317 cube number measure
If a cube number do not measure a cube number, neither will the side measure the side; and, if the side do not measure the side, neither will the cube measure the cube.
G.318 similar plane and solid numbers
Similar plane and solid numbers are those which have their sides:term:proportional <G.180>.
G.319 similar plane numbers
Between two similar plane numbers there is one mean proportional number; and the plane number has to the plane number the ratio duplicate of that which the corresponding side has to the corresponding side.
G.320 square and cube numbers
And, when three:term:numbers <G.248> having:term:multiplied <G.269> one another make some number, the number so produced is:term:**solid** <solid-number>, and its:term:**sides** <side-of-number> are the numbers which have multiplied one another.
G.321 similar solid numbers
Between two similar solid numbers there fall two mean proportional numbers; and the solid number has to the similar solid number the ratio triplicate of that which the corresponding side has to the corresponding side.
G.322 mean proportional number
If one mean proportional number fall between two numbers, the numbers is similar plane numbers.
G.323 mean proportional numbers
If two mean proportional numbers fall between two numbers, the numbers are similar solid numbers.
G.324 numbers continued proportion
If three numbers be in continued proportion, and the first be square, the third is square.
G.325 numbers continued proportion
If four numbers be in continued proportion, and the first be cube, the fourth is cube.
G.326 numbers ratio square
If two numbers have to one another the ratio which a square number has to a square number, and the first be square, the second is square.
G.327 numbers ratio cube
If two numbers have to one another the ratio which a cube number has to a cube number, and the first be cube, the second is cube.
G.328 similar plane numbers
Similar plane numbers have to one another the ratio which a square number has to a square number.
G.329 similar solid numbers
Similar solid numbers have to one another the ratio which a cube number has to a cube number.
G.330 similar plane numbers
If two similar plane numbers by multiplying one another make some number, the product is square.
G.331 numbers multiplying make
If two numbers by multiplying one another make a square number, they are similar plane numbers.
G.332 cube number multiplying
If a cube number by multiplying itself make some number, the product is cube.
G.333 cube number multiplying
If a cube number by multiplying a cube number make some number, the product is cube.
G.334 cube number multiplying
If a cube number by multiplying any number make a cube number, the multiplied number is cube.
G.335 number multiplying itself
If a number by multiplying itself make a cube number, it will itself also be cube.
G.336 composite number multiplying
If a composite number by multiplying any number make some number, the product is solid.
G.337 many numbers please
If as many numbers as we please beginning from an unit be in continued proportion, the third from the unit is square, as will also those which successively leave out one; the fourth is cube, as will also all those which leave out two; and the seventh is at once cube and square, as will also those which leave out five.
G.338 many numbers please
If as many numbers as we please beginning from an unit be in continued proportion, and the number after the unit be square, all the rest is square. And, if the number after the unit be cube, all the rest is cube.
G.339 many numbers please
If as many numbers as we please beginning from an unit be in continued proportion, and the number after the unit be not square, neither will any other be square except the third from the unit and all those which leave out one. And, if the number after the unit be not cube, neither will any other be cube except the fourth from the unit and all those which leave out two.
G.340 many numbers please
If as many numbers as we please beginning from an unit be in continued proportion, the less measures the greater according to some one of the numbers which have place among the proportional numbers.
G.341 numbers composite to one another
Numbers composite to one another are those which are:term:measured <G.253> by some:term:number <G.248> as a common measure.
G.342 many numbers please
If as many numbers as we please beginning from an unit be in continued proportion, by however many prime numbers the last is measured, the next to the unit is measured by the same.
G.343 many numbers please
If as many numbers as we please beginning from an unit be in continued proportion, and the number after the unit be prime, the greatest will not be measured by any except those which have a place among the proportional numbers.
G.344 number least measured
If a number be the least that is measured by prime numbers, it will not be measured by any other prime number except those originally measuring it.
G.345 numbers continued proportion
If three numbers in continued proportion be the least of those which have the same ratio with them, any two whatever added together is prime to the remaining number.
G.346 numbers prime number
If two numbers be prime to one another, the second will not be to any other number as the first is to the second.
G.347 there many numbers
If there be as many numbers as we please in continued proportion, and the extremes of them be prime to one another, the last will not be to any other number as the first to the second.
G.348 numbers investigate whether
Given two numbers, to investigate whether it is possible to find a third proportional to them.
G.349 numbers investigate possible
Given three numbers, to investigate when it is possible to find a fourth proportional to them.
G.350 prime numbers more
Prime numbers are more than any assigned multitude of prime numbers.
G.351 many even numbers
If as many even numbers as we please be added together, the whole is even.
G.352 odd number
An:term:**odd number** <odd-number> is that which is not divisible into two equal parts, or that which differs by an:term:unit <G.247> from an:term:even number <G.302>.
G.353 many odd numbers
If as many odd numbers as we please be added together, and their multitude be even, the whole is even.
G.354 many odd numbers
If as many odd numbers as we please be added together, and their multitude be odd, the whole is odd.
G.355 even number even
If from an even number an even number be subtracted, the remainder is even.
G.356 even number odd
If from an even number an odd number be subtracted, the remainder is odd.
G.357 odd number odd
If from an odd number an odd number be subtracted, the remainder is even.
G.358 odd number even
If from an odd number an even number be subtracted, the remainder is odd.
G.359 odd number multiplying
If an odd number by multiplying an even number make some number, the product is even.
G.360 odd number multiplying
If an odd number by multiplying an odd number make some number, the product is odd.
G.361 odd number measure
If an odd number measure an even number, it will also measure the half of it.
G.362 odd number prime
If an odd number be prime to any number, it is prime to the double of it.
G.363 even-times even number
An:term:**even-times even number** <even-times-even-number> is that which is:term:measured <G.253> by an:term:even number <G.302> according to an even number.
G.364 numbers continually doubled
Each of the numbers which are continually doubled beginning from a dyad is even-times even only.
G.365 even-times odd number
An:term:**even-times odd number** <even-times-odd-number> is that which is:term:measured <G.253> by an:term:even number <G.302> according to an:term:odd number <G.352>.
G.366 number half odd
If a number have its half odd, it is even-times odd only.
G.367 number continually doubled
If a number neither be one of those which are continually doubled from a dyad, nor have its half odd, it is both even-times even and even-times odd.
G.368 many numbers please
If as many numbers as we please be in continued proportion, and there be subtracted from the second and the last numbers equal to the first, then, as the excess of the second is to the first, so will the excess of the last be to all those before it.
G.369 perfect number
A:term:**perfect number** <perfect-number> is that which is equal to its own parts.
G.370 many numbers please
If as many numbers as we please beginning from an unit be set out continuously in double proportion, until the sum of all becomes prime, and if the sum multiplied into the last make some number, the product is perfect.