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%I #13 Oct 24 2019 10:26:56
%S 1,1,1,2,3,2,7,12,12,7,38,69,81,69,38,295,552,702,702,552,295,3098,
%T 5901,7857,8559,7857,5901,3098,42271,81444,111618,128034,128034,
%U 111618,81444,42271,726734,1411197,1971945,2339631,2467665,2339631,1971945
%N Triangle of numbers associated with Genocchi numbers.
%H G. Kreweras, <a href="https://doi.org/10.1006/eujc.1995.0081">Sur les permutations comptées par les nombres de Genocchi de 1-ière et 2-ième espèce</a>, Europ. J. Comb., vol. 18, pp. 49-58, 1997.
%H G. Kreweras and D. Dumont, <a href="http://dx.doi.org/10.1016/S0012-365X(99)00238-1">Sur les anagrammes alternés</a>, Discrete Mathematics, Volume 211, Issues 1-3, 28 January 2000, Pages 103-110. Zbl 0944.05003.
%t a[ 1, 1 ]=1; a[ n_, k_ ] := 0 /; (k>n || k<=0); a[ n_, 1 ]=Sum[ a[ n-1, i ], {i, 1, n-1} ] a[ n_, k_ ] := a[ n, k ]=2a[ n, k-1 ]-a[ n, k-2 ]-a[ n-1, k-1 ]-a[ n-1, k-2 ]; Flatten[ Table[ a[ n, i ], {n, 1, 10}, {i, 1, n} ] ]
%Y Cf. A035003.
%Y Columns include A000366 and A102078. Row sums are in A000366.
%K tabl,nonn,easy
%O 0,4
%A _N. J. A. Sloane_.
%E More terms from _Erich Friedman_.
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