cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A353632 Even bisection of A353630: Arithmetic derivative of primorial base exp-function, reduced modulo 4, computed for even numbers.

Original entry on oeis.org

0, 1, 2, 1, 0, 3, 2, 3, 0, 3, 2, 1, 0, 1, 2, 1, 2, 3, 0, 3, 2, 3, 0, 1, 2, 1, 0, 1, 2, 3, 2, 3, 0, 3, 2, 1, 0, 1, 2, 1, 0, 3, 2, 3, 0, 3, 0, 1, 2, 1, 0, 1, 2, 3, 0, 3, 2, 3, 0, 1, 0, 1, 2, 1, 0, 3, 2, 3, 0, 3, 2, 1, 0, 1, 2, 1, 2, 3, 0, 3, 2, 3, 0, 1, 2, 1, 0, 1, 2, 3, 2, 3, 0, 3, 2, 1, 0, 1, 2, 1, 0, 3, 2, 3, 0, 1
Offset: 0

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Author

Antti Karttunen, May 01 2022

Keywords

Crossrefs

Even bisection of A353630. A353631 gives the odd bisection.
Cf. also A353487, A353642.

Programs

  • PARI
    A353630(n) = { my(s=0, m=1, p=2, e); while(n, e = (n%p); m *= (p^e); s += (e/p); n = n\p; p = nextprime(1+p)); ((s*m)%4); };
    A353632(n) = A353630(n+n);

Formula

a(n) = A353630(2*n) = A010873(A327860(2*n)).
A000035(a(n)) = A000035(n).