Math One Liners

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This page is dedicated to showcase small snippets of code that may be useful. These small routines are designed to accomplish tasks involving mathematics. Unless specified, output is in Ans.

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Primality of Positive Integer – jonbush; lirtosiast

This routine works for 3≤X<10⁶ and returns 0 if X is composite, and 1 if X is prime.
If used in an If statement or place where the true value does not matter, you can remove the 0≠.

min(remainder(X,seq(A,A,2,1+√(X

This code can be modified to be faster if X is already known to be odd.

min(remainder(X,seq(A,A,3,1+√(X),2

The following code is faster for large or even X, and works for all 0≤X<3.99*10⁶.

min(X={2,3,5
If X≥7 and fPart(.5X
min(remainder(X,3+2cumSum(not(binompdf(int(.5√(X)),0

Euler's Totient Function Φ(n) – kg583

This routine calculates the value of Euler's Totient Function for any integer X>3.

2+sum(seq(gcd(X,A)=1,A,2,X-2

Number of Factors – kg583

This routine calculates the number of factors for any integer X>2. A factor is any integer can divide X with no remainder (including 1 and X).

2+Xmean(seq(not(remainder(X,A),A,2,X-2

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