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A171509
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Riordan array (f(x), x*f(x)) where f(x) is the g.f. of A126931.
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0
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1, 3, 1, 10, 6, 1, 33, 29, 9, 1, 110, 126, 57, 12, 1, 366, 518, 306, 94, 15, 1, 1220, 2052, 1494, 600, 140, 18, 1, 4065, 7925, 6849, 3389, 1035, 195, 21, 1, 13550, 30030, 30025, 17628, 6635, 1638, 259, 24, 1
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OFFSET
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0,2
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COMMENTS
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Equal to A053121*B^3, B = A007318.
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LINKS
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Table of n, a(n) for n=0..44.
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FORMULA
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Sum_[k, 0<=k<=n} T(n,k)*x^k = A126930(n), A126120(n), A001405(n), A054341(n), A126931(n) for x = -4, -3, -2, -1, 0 respectively.
T(n,k) = T(n-1,k-1) + 3*T(n-1,k) + sum_{i, i>=0} T(n-1,k+1+i)*(-3)^i. - Philippe Deléham, Feb 23 2012
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EXAMPLE
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Triangle begins : 1 ; 3,1 ; 10,6,1 ; 33,29,9,1 ; 110,126,57,12,1 ; ...
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CROSSREFS
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Cf. A053121, A054336, A096164, A171505
Sequence in context: A113187 A057967 A132964 * A171505 A134283 A035324
Adjacent sequences: A171506 A171507 A171508 * A171510 A171511 A171512
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KEYWORD
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nonn,tabl
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AUTHOR
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Philippe DELEHAM, Dec 10 2009
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STATUS
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approved
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