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Expansion of c(x*y(1+x)), c(x) the g.f. of A000108.
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%I #14 Sep 08 2022 08:45:24

%S 1,0,1,0,1,2,0,0,4,5,0,0,2,15,14,0,0,0,15,56,42,0,0,0,5,84,210,132,0,

%T 0,0,0,56,420,792,429,0,0,0,0,14,420,1980,3003,1430,0,0,0,0,0,210,

%U 2640,9009,11440,4862,0,0,0,0,0,42,1980,15015,40040,43758,16796,0,0,0,0,0,0,792,15015,80080,175032,167960,58786

%N Expansion of c(x*y(1+x)), c(x) the g.f. of A000108.

%H G. C. Greubel, <a href="/A117434/b117434.txt">Rows n = 0..50 of the triangle, flattened</a>

%H Jian Zhou, <a href="https://arxiv.org/abs/2108.10514">On Some Mathematics Related to the Interpolating Statistics</a>, arXiv:2108.10514 [math-ph], 2021.

%F T(n, k) = binomial(k, n-k)*Catalan(k).

%F Sum_{k=0..n} T(n, k) = A052709(n+1).

%F Sum_{k=0..floor(n/2)} T(n-k, k) = A115178(n) (upward diagonal sums).

%F T(n, k) = (-1)^(n+k)*A115179(n, k).

%e Triangle begins as:

%e 1;

%e 0, 1;

%e 0, 1, 2;

%e 0, 0, 4, 5;

%e 0, 0, 2, 15, 14;

%e 0, 0, 0, 15, 56, 42;

%e 0, 0, 0, 5, 84, 210, 132;

%e 0, 0, 0, 0, 56, 420, 792, 429;

%t Table[CatalanNumber[k]*Binomial[k, n-k], {n,0,12}, {k,0,n}]//Flatten (* _G. C. Greubel_, May 31 2021 *)

%o (Magma) [Binomial(k, n-k)*Catalan(k): k in [0..n], n in [0..12]]; // _G. C. Greubel_, May 31 2021

%o (Sage) flatten([[binomial(k, n-k)*catalan_number(k) for k in (0..n)] for n in (0..12)]) # _G. C. Greubel_, May 31 2021

%Y Cf. A000108, A052709, A115178, A115178.

%K easy,nonn,tabl

%O 0,6

%A _Paul Barry_, Mar 14 2006