A104561 - OEIS

%I #3 Mar 30 2012 18:36:45

%S 1,-1,1,-2,6,-30,204,-1944,23340,-360060,6692280,-151908120,

%T 4032593040,-126425330640,4537069829880,-187762669281600,

%U 8751745668796200,-462088269954518760,27132285729049971120,-1779812144439507990000,128512316060872730854560

%N Column 0 of triangle A104560.

%C A104560 equals the matrix inverse of A104559, where A104559(n,k) = C(n-[k/2],[(k+1)/2])*C(n-[(k+1)/2],[k/2]).

%o (PARI) {a(n)=local(M);M=matrix(n+1,n+1,m,j,if(m>=j, binomial(m-1-(j-1)\2,j\2)*binomial(m-1-j\2,(j-1)\2))); return((M^-1)[n+1,1])}

%Y Cf. A104559, A104560.

%K sign

%O 0,4

%A _Paul D. Hanna_, Mar 16 2005