A131307 - OEIS

A131307

(A127701 * A000012 + A000012(signed) * A127701) - A000012.

1, 2, 3, 3, 2, 5, 4, 5, 2, 7, 5, 4, 7, 2, 9, 6, 7, 4, 9, 2, 11, 7, 6, 9, 4, 11, 2, 13, 8, 9, 6, 11, 4, 13, 2, 15, 9, 8, 11, 6, 13, 4, 15, 2, 17, 10, 11, 8, 13, 6, 15, 4, 17, 2, 19

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OFFSET

1,2

COMMENTS

Row sums = A035608: (1, 5, 10, 18, 27, 39, 52, ...).

LINKS

Table of n, a(n) for n=1..55.

FORMULA

(A127701 * A000012 + A000012(signed) * A127701) - A000012; as infinite lower triangular matrices, where A000012(signed) = (1; -1,1; 1,-1,1; -1,1,-1,1; ...).

EXAMPLE

First few rows of the triangle:

2, 3;

3, 2, 5;

4, 5, 2, 7;

5, 4, 7, 2, 9;

6, 7, 4, 9, 2, 11;

7, 6, 9, 4, 11, 2, 13;

8, 9, 6, 11, 4, 13, 2, 15;

9, 8, 11, 6, 13, 4, 15, 2, 17;

10, 11, 8, 13, 6, 15, 4, 17, 2, 19;

...