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%I #8 Apr 30 2014 01:34:23
%S 1,5,0,2295,453871,0,545539395584,4883188189089105,0,
%T 14214363393075742724609375,5968603205606800870499639536231,0,
%U 41302584753289717847206700750464023881130441
%N From Wendt's determinant compute (A048954(2*n)/(1-4^n))^(1/2).
%D P. Ribenboim, 13 Lectures on Fermat's last theorem, Springer-Verlag, NY, 1979, page 62. MR0551363 (81f:10023)
%F a(n)=0 if and only if n is divisible by 3.
%F a(n) = A215615(2*n). - _Jonathan Sondow_, Aug 17 2012
%o (PARI) {a(n)= if(n<1, 0, n*=2; sqrtint( matdet( matrix( n, n, i, j, binomial( n, (j-i)%n )))/ (1-2^n)))}
%Y Cf. A048954, A215615, A215616.
%K nonn
%O 1,2
%A _Michael Somos_, Apr 03 2007