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%I #14 Apr 28 2016 12:41:46
%S 1,1,1,1,1,1,1,1,1,1,3,2,1,1,5,4,1,1,7,6,1,1,1,9,8,6,3,1,1,11,10,15,
%T 10,1,1,13,12,28,21,1,1,1,15,14,45,36,10,4,1,1,17,16,66,55,35,20,1,1,
%U 19,18,91,78,84,56,1,1,1,21,20,120,105,165,120,15,5,1
%N Triangle of rising diagonals of A011973 (with rows displayed as centered text).
%C Row sums are A227300
%F r(n) = binomial[2n-k-2-3floor(k/2),floor(k/2)); {k, 0,...,floor((2n-1)/3)}. - _John Molokach_, Jul 29 2013
%e Triangle begins:
%e 1;
%e 1, 1;
%e 1, 1;
%e 1, 1, 1;
%e 1, 1, 3, 2;
%e 1, 1, 5, 4;
%e 1, 1, 7, 6, 1;
%e 1, 1, 9, 8, 6, 3;
%e 1, 1, 11, 10, 15, 10;
%e 1, 1, 13, 12, 28, 21, 1;
%t Table[Binomial[2 n - k - 2 - 3 Floor[k/2], Floor[k/2]], {n, 1, 25}, {k, 0, Floor[(2 n - 1)/3]}] (* _John Molokach_, Jul 29 2013 *)
%Y Cf. A011973, A000045, A227300, A005314, A224838.
%K nonn,tabf
%O 1,11
%A _John Molokach_, Jul 27 2013
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