A144220 - OEIS

A144220

Triangle read by rows, A118433 (the self-inverse triangle) * A000012^(-1).

1, 2, -1, -3, 1, 1, -4, 0, 4, -1, 5, 2, -10, 3, 1, 6, 5, -20, 5, 6, -1, -7, -9, 35, 5, -21, 5, 1, -8, -14, 56, 0, -56, 14, 8, -1, 9, 20, -84, -14, 126, -28, -36, 7, 1, 10, 27, -120, -42, 252, -42, -120, 27, 10, -1, -11, -35, 165, 90, -462, 42, 330, -75, -55, 9, 1

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OFFSET

0,2

COMMENTS

Row sums = (1, 1, -1, -1, 1, 1, ...).

LINKS

Table of n, a(n) for n=0..65.

FORMULA

A118433 * A000012^(-1), where A000012^(-1) is an infinite lower triangular matrix with 1's in the main diagonal and (-1)'s in the subdiagonal, with the rest zeros.

EXAMPLE

First few rows of the triangle:

2, -1;

3, 1, 1;

-4, 0, 4, -1

5, 2, -10, 3, 1;

6, 5, -20, 5, 6, -1;

-7, -9, 35, -5, -21, 5, 1;

-8, -14, 56, 0, -56, 14, 8, -1;

9, 20, -84, -14, 126, -28, -36, 7, 1;

10, 27, -120, -42, 252, -42, -120, 27, 10, -1;

...