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%I #11 Jun 14 2017 00:58:27
%S 1,-3,70,-11160,12850368,-111842970624,7558738517524480,
%T -4024873276683363287040,17013427111087951089139449856,
%U -573105858480900876266937950612226048,154142404695090288939416498797330749299097600
%N Central terms of triangle A135950, the matrix inverse of triangle A022166.
%C A022166 is the triangle of Gaussian binomial coefficients [n,k] for q = 2.
%t max = 20; M = Table[QBinomial[n, k, 2], {n, 0, max}, {k, 0, max}] // Inverse; Table[M[[n, (n+1)/2]], {n, 1, max+1, 2}] (* _Jean-François Alcover_, Apr 09 2016 *)
%t Table[(-1)^n 2^((n-1)n/2) QBinomial[2n, n, 2], {n, 0, 20}] (* _Vladimir Reshetnikov_, Sep 16 2016 *)
%o (PARI) a(n)=local(q=2,A=matrix(2*n+1,2*n+1,n,k,if(n>=k,if(n==1 || k==1, 1, prod(j=n-k+1, n-1, 1-q^j)/prod(j=1, k-1, 1-q^j))))^-1);A[2*n+1,n+1]
%Y Cf. A135950, A022166.
%K sign
%O 0,2
%A _Paul D. Hanna_, Dec 08 2007