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%I #5 Mar 30 2012 18:37:04
%S 1,1,-2,12,-118,1605,-27816,585046,-14459138,410368743,-13146830110,
%T 469123986529,-18447791712945,792514583941223,-36925394368325295,
%U 1854525584914459755,-99872579714406393286,5740977285851988017769,-350847888975706702249890
%N Column 1 of triangle A132690.
%C Appears to be essentially a signed version of A121425. - _N. J. A. Sloane_, Oct 30 2008
%C Triangle T=A132690 is generated from negative powers of itself such that row n+1 of T = row n of T^(-n) with appended '1' for n>=0 with T(0,0)=1.
%o (PARI) {a(n)=local(A=Mat(1), B); for(m=1, n+2, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i, B[i, j]=1, B[i, j]=(A^(-(i-2)))[i-1, j]); )); A=B); return( ((A)[n+2,2]))}
%Y Cf. A132690; A132691, A132693, A132694, A121425.
%K sign
%O 0,3
%A _Paul D. Hanna_, Aug 25 2007
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