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.

A348127 Product_{n>=1} 1 / (1 - a(n)*x^n) = 1 + Sum_{n>=1} x^prime(n).

Original entry on oeis.org

0, 1, 1, -1, 0, -1, 1, -1, -1, -1, 2, 0, 0, -3, 0, 0, 3, -3, -1, -1, 4, -4, -1, -5, 6, 2, 2, -17, 4, 4, 13, -16, -7, -11, 30, -14, -7, -34, 42, 7, 16, -80, 27, 6, 95, -117, -21, -60, 223, -97, -48, -265, 326, 53, 129, -800, 242, 93, 752, -948, -105, -499, 1806, -853, -240, -2189, 2750, 124
Offset: 1

Views

Author

Ilya Gutkovskiy, Oct 01 2021

Keywords

Crossrefs

Programs

  • Maple
    N:= 20: # for a(1)..a(N)
    P:= 1: a:= Vector(N):
    for n from 1 to N do
      c:= coeff(P,x,n);
      if isprime(n) then a[n]:= 1-c  else a[n]:= -c fi;
      P:= series(P/(1-a[n]*x^n),x,N+1);
    od:
    convert(a,list); # Robert Israel, Mar 01 2022