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.

A111967 Inverse of number triangle A101688.

Original entry on oeis.org

1, 0, 1, 0, -1, 1, 0, 1, -1, 1, 0, 0, 0, -1, 1, 0, -1, 1, 0, -1, 1, 0, 0, 0, 0, 0, -1, 1, 0, 1, -1, 1, 0, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0, -1, 1, 0, 0, 0, -1, 1, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1, 0, -1, 1, 0, -1, 1, 0, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1
Offset: 0

Views

Author

Paul Barry, Aug 23 2005

Keywords

Comments

Row sums are the Fredholm-Rueppel sequence A036987 [conjecture].

Examples

			Triangle begins
1,
0, 1,
0, -1, 1,
0, 1, -1, 1,
0, 0, 0, -1, 1,
0, -1, 1, 0, -1, 1,
0, 0, 0, 0, 0, -1, 1,
0, 1, -1, 1, 0, 0, -1, 1,
0, 0, 0, 0, 0, 0, 0, -1, 1,
0, 0, 0, -1, 1, 0, 0, 0, -1, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1,
0, -1, 1, 0, -1, 1, 0, 0, 0, 0, -1, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1,
0, 0, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, -1, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1,
0, 1, -1, 1, 0, 0, -1, 1, 0, 0, 0, 0, 0, 0, -1, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1
		

Crossrefs

Programs

  • PARI
    T(n, k) = if(binomial(k, n-k)>0, 1, 0); \\ A101688
    mrepeat(nn) = matrix(nn, nn, n, k, T(n-1, k-1)); \\ A101688
    lista(nn) = my(m=mrepeat(nn+1), im = 1/m, list = List()); for (n = 1, nn, listput(list, vector(n, k, im[n,k]));); Vec(list); \\ Michel Marcus, Nov 12 2022

Formula

G.f. of k-th column is x^k*if(k=0,1,x*Sum_{j>=0} (-1)^j*x^(-2^(j/2)*(((k+2)/(2*sqrt(2))-(k+1))(-1)^j-(k+2)/(2*sqrt(2))-(k+1))-(k+2))+1-x). - Paul Barry, Jan 30 2007