A158946 - OEIS

A158946

Triangle read by rows, A000012(signed) * A145677 * A000012

1, 1, 1, 2, 1, 2, 2, 2, 1, 3, 3, 2, 3, 1, 4, 3, 3, 2, 4, 1, 5, 4, 3, 4, 2, 5, 1, 6, 4, 4, 3, 5, 2, 6, 1, 7, 5, 4, 5, 3, 6, 2, 7, 1, 8, 5, 5, 4, 6, 3, 7, 2, 8, 1, 9, 6, 5, 6, 4, 7, 3, 8, 2, 9, 1, 10, 6, 6, 5, 7, 4, 8, 3, 9, 2, 10, 1, 11

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OFFSET

1,4

COMMENTS

Row sums = A000982 starting with offset 1: (1, 2, 5, 8, 13, 18, 25,...).

LINKS

Table of n, a(n) for n=1..78.

FORMULA

Triangle read by rows, A000012(signed) * A145677 * A000012. A000012(signed) = an infinite lower triangular matrix with (1,-1,1,-1,...) in every column. A145677 = an infinite lower triangular matrix with all 1's as the left border, right border = (1, 1, 2, 3, 4, 5,...), and the rest zeros.

EXAMPLE

First few rows of the triangle =

1, 1;

2, 1, 2;

2, 2, 1, 3;

3, 2, 3, 1, 4;

3, 3, 2, 4, 1, 5;

4, 3, 4, 2, 5, 1, 6;

4, 4, 3, 5, 2, 6, 1, 7;

5, 4, 5, 3, 6, 2, 7, 1, 8;

5, 5, 4, 6, 3, 7, 2, 8, 1, 9;

6, 5, 6, 4, 7, 3, 8, 2, 9, 1, 10;