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%I #3 Mar 30 2012 18:36:38
%S 1,1,1,0,2,2,-1,1,6,5,-2,-2,6,20,14,-3,-6,-4,30,70,42,-4,-10,-24,0,
%T 140,252,132,-5,-13,-48,-95,70,630,924,429,-6,-14,-66,-240,-350,588,
%U 2772,3432,1430,-7,-12,-66,-370,-1176,-1134,3696,12012,12870,4862,-8,-6,-36,-380,-2100,-5544,-2772,20592,51480,48620,16796
%N Triangle of coefficients, read by rows, where T(n,k) is the coefficient of x^n*y^k in f(x,y) that satisfies f(x,y) = 1/(1-x) - x^2/(1-x)^2 + xy*f(x,y)^2.
%C The main diagonal gives the Catalan sequence A000108. Antidiagonal sums results in all 1's. Row sums give A086611.
%e Rows:
%e {1},
%e {1,1},
%e {0,2,2},
%e {-1,1,6,5},
%e {-2,-2,6,20,14},
%e {-3,-6,-4,30,70,42},
%e {-4,-10,-24,0,140,252,132},
%e {-5,-13,-48,-95,70,630,924,429},
%e {-6,-14,-66,-240,-350,588,2772,3432,1430},
%e {-7,-12,-66,-370,-1176,-1134,3696,12012,12870,4862}, ...
%Y Cf. A086611 (row sums), A086632.
%K sign,tabl
%O 0,5
%A _Paul D. Hanna_, Jul 24 2003