cp's OEIS Frontend

A111526 Number triangle T(n,k)=C((n+k)/2,k)(n+1)(1+(-1)^(n-k))/(2(k+1)); T(n,k)=(-1)^((n-k)/2)*A053120(n+1,k+1)/2^k; Riordan array ((1+x^2)/(1-x^2)^2,x/(1-x^2)).

%I A111526 #2 Mar 30 2012 18:59:09
%S A111526 1,0,1,3,0,1,0,4,0,1,5,0,5,0,1,0,9,0,6,0,1,7,0,14,0,7,0,1,0,16,0,20,0,
%T A111526 8,0,1,9,0,30,0,27,0,9,0,1,0,25,0,50,0,35,0,10,0,1,11,0,55,0,77,0,44,
%U A111526 0,11,0,1,0,36,0,105,0,112,0,54,0,12,0,1,13,0,91,0,182,0,156,0,65,0,13,0,1,0
%N A111526 Number triangle T(n,k)=C((n+k)/2,k)(n+1)(1+(-1)^(n-k))/(2(k+1)); T(n,k)=(-1)^((n-k)/2)*A053120(n+1,k+1)/2^k; Riordan array ((1+x^2)/(1-x^2)^2,x/(1-x^2)).
%C A111526 A scaled Chebyshev triangle.
%C A111526 Row sums are A001350(n+1). Diagonal sums are A033484, with interpolated zeros. Inverse is A111527.
%e A111526 Triangle starts
%e A111526 1;
%e A111526 0,1;
%e A111526 3,0,1;
%e A111526 0,4,0,1;
%e A111526 5,0,5,0,1;
%e A111526 0,9,0,6,0,1;
%e A111526 7,0,14,0,7,0,1;
%Y A111526 Cf. A110813.
%K A111526 easy,nonn,tabl
%O A111526 0,4
%A A111526 _Paul Barry_, Aug 05 2005