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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.
0
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)).
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
Sequence in context: A137320 A263399 A143507 * A317327 A120557 A092594
KEYWORD
nonn,tabl
AUTHOR
Philippe Deléham, Jan 23 2010
STATUS
approved