A144159 - OEIS

A144159

Eigentriangle, sum of row n terms = A006054(n+2).

1, 1, 1, 2, 1, 2, 2, 2, 2, 5, 3, 2, 4, 5, 11, 3, 3, 4, 10, 11, 25, 4, 3, 6, 10, 22, 25, 56, 4, 4, 6, 15, 22, 50, 56, 126, 5, 4, 8, 15, 33, 50, 112, 126, 283, 5, 5, 8, 20, 33, 75, 112, 252, 283, 636

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OFFSET

1,4

COMMENTS

Left border = (1, 1, 2, 2, 3, 3,...) Row sums = (1, 2, 5, 11, 25, 56, 126,...) = A006054 such that row n = A006054(n+2).

Sum of n-th row terms = rightmost term of next row.

LINKS

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

FORMULA

Triangle read by rows, A * B, where A = an infinite lower triangular matrix with A008619: (1, 1, 2, 2, 3, 3,...) in every column. B = an infinite lower triangular matrix with A008619 as the main diagonal: (1, 2, 5, 11, 25, 56, 126,...) and the rest zeros.

EXAMPLE

First few rows of the triangle =

1, 1;

2, 1, 2;

2, 2, 2, 5;

3, 2, 4, 5, 11;

3, 3, 4, 10, 11, 25;

4, 3, 6, 10, 22, 25, 56;

4, 4, 6, 15, 22, 50, 56, 126;

5, 4, 8, 15, 33, 50, 112, 126, 283;

...

CROSSREFS