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

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 ;
  0,2 ;
  0,2,4 ;
  0,6,8,8 ;
  0,22,28,24,16 ; ...

Crossrefs

Cf. A104219, A108891.

Sequence in context: A137320 A263399 A143507 * A317327 A120557 A092594

Adjacent sequences: A172037 A172038 A172039 * A172041 A172042 A172043

Keyword

nonn,tabl,changed

Author

Philippe Deléham, Jan 23 2010

Status

approved