0,4

Row sums = A000984: (1, 2, 6, 20, 70, 252,...), left border = A081696.

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

Triangle read by rows, M*Q. M = an infinite lower triangular matrix with A081696:

(1, 1, 3, 9, 29, 97, 333, 1165,...) in every column; and Q = a matrix with

A000984 as the main diagonal (prefaced with a 1): (1, 1, 2, 6, 20, 70, 252,...) and the rest zeros.

First few rows of the triangle =

1;

1, 1;

3, 1, 2;

9, 3, 2, 6;

29, 9, 6, 6, 20;

97, 29, 18, 18, 20, 70;

333, 97, 58, 54, 60, 70, 252;

1165, 333, 194, 174, 180, 210, 252, 924;

4135, 1165, 666, 582, 580, 630, 756, 924, 3432;

14845, 4135, 2330, 1998, 1940, 2030, 2268, 2772, 3432, 12870;

...

Row 3 = (9, 3, 2, 6) = termwise products of (9, 3, 1, 1) and (1, 1, 2, 6).

A000984, A081696

Sequence in context: A086961 A085194 A152252 this_sequence A074308 A058142 A058144

Adjacent sequences: A152226 A152227 A152228 this_sequence A152230 A152231 A152232

nonn,tabl

Gary W. Adamson (qntmpkt(AT)yahoo.com), Nov 29 2008