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%I #19 Oct 22 2019 04:20:58
%S 1,1,3,1,1,1,1,1,1,5,1,3,1,1,1,1,1,1,1,1,7,1,1,1,1,1,1,1,1,3,1,1,1,1,
%T 1,1,1,1,1,5,1,1,1,1,1,1,1,1,1,1,1,1,1,1,11,1,3,1,1,1,1,1,1,1,1,1,1,1,
%U 1,1,1,1,1,1,1,1,1,13,1,1,1,1,1,7,1,1,1,1,1,1,1,1,3,1,5,1,1,1,1,1,1,1,1,1,1
%N Triangle read by rows: T(n,k) is the denominator of f(n, k) = (Product_{i = 0..k-1} (n-i))/(Sum_{i = 1..k} i) for 1 <= k <= n.
%F T(n,n) = denominator(f(n, n)) = denominator(2*(n-1)!/(n+1)).
%e Triangle T(n,k) (with rows n >= 1 and columns k >= 1) begins as follows:
%e 1;
%e 1, 3;
%e 1, 1, 1;
%e 1, 1, 1, 5;
%e 1, 3, 1, 1, 1;
%e 1, 1, 1, 1, 1, 7;
%e 1, 1, 1, 1, 1, 1, 1;
%e 1, 3, 1, 1, 1, 1, 1, 1;
%e 1, 1, 1, 5, 1, 1, 1, 1, 1;
%e 1, 1, 1, 1, 1, 1, 1, 1, 1, 11;
%e ...
%Y Cf. A090585, A090586, A093415, A093420 (numerators), A093423.
%K nonn,easy,frac,tabl,less
%O 1,3
%A _Amarnath Murthy_, Mar 30 2004
%E Edited and extended by _David Wasserman_, Aug 29 2006