

A207327


Riordan array (1, x*(1+x)^2/(1x)).


0



1, 0, 1, 0, 3, 1, 0, 4, 6, 1, 0, 4, 17, 9, 1, 0, 4, 32, 39, 12, 1, 0, 4, 48, 111, 70, 15, 1, 0, 4, 64, 240, 268, 110, 18, 1, 0, 4, 80, 432, 769, 530, 159, 21, 1, 0, 4, 96, 688, 1792, 1905, 924, 217, 24, 1, 0, 4
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OFFSET

0,5


COMMENTS

Triangle T(n,k), read by rows, given by (0, 3, 5/3, 4/15, 3/5, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938.
Row sums are A077995(n).


LINKS

Table of n, a(n) for n=0..56.


FORMULA

T(2*n,n) = A119259(n).
G.f.: (1x)/(1(1+y)*x2*y*x^2y*x^3).
T(n,k) = T(n1,k) + T(n1,k1) + 2*T(n2,k1) + T(n3,k1), T(0,0) = 1, T(1,0) = 0.


EXAMPLE

Triangle begins :
1
0, 1
0, 3, 1
0, 4, 6, 1
0, 4, 17, 9, 1
0, 4, 32, 39, 12, 1
0, 4, 48, 111, 70, 15, 1
0, 4, 64, 240, 268, 110, 18, 1
0, 4, 80, 432, 769, 530, 159, 21, 1
0, 4, 96, 688, 1792, 1905, 924, 217, 24, 1
0, 4, 112, 1008, 3584, 5503, 3999, 1477, 284, 27, 1
0, 4, 128, 1392, 6400, 13440, 13842, 7483, 2216, 360, 30, 1


CROSSREFS

Cf. Diagonals : A000012, A008585, A022266, A000007, A113311
Sequence in context: A212186 A274662 A186827 * A319083 A045406 A143468
Adjacent sequences: A207324 A207325 A207326 * A207328 A207329 A207330


KEYWORD

easy,nonn,tabl


AUTHOR

Philippe Deléham, Feb 17 2012


STATUS

approved



