A172040 - OEIS

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A172040

Triangle T(n,k), read by rows, given by [0,1,2,1,2,1,2,1,2,1,2,...] DELTA [2,0,0,0,0,0,0,0,0,...] where DELTA is the operator defined in A084938.

1, 0, 2, 0, 2, 4, 0, 6, 8, 8, 0, 22, 28, 24, 16, 0, 90, 112, 96, 64, 32, 0, 394, 484, 416, 288, 160, 64, 0, 1806, 2200, 1896, 1344, 800, 384, 128, 0, 8558, 10364, 8952, 6448, 4000, 2112, 896, 256, 0, 41586, 50144, 43392, 31616, 20160, 11264, 5376, 2048, 512, 0

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OFFSET

0,3

COMMENTS

Riordan array (1, 2x*f(x)) where f(x) is the g.f. of A001003. Riordan production matrix is : (0, (2-x)/(1-x)).

LINKS

Table of n, a(n) for n=0..55.

FORMULA

Sum_{k=0..n} T(n,k) = A006318(n).

EXAMPLE

Triangle begins:

1 ;