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From Wendt's determinant compute sqrt(abs(A048954(n))/(2^n - 1)).
5

%I #11 Aug 18 2012 14:09:56

%S 1,1,2,5,11,0,232,2295,26714,453871,7053157,0,7715707299,545539395584,

%T 42297694603648,4883188189089105,531361846217471443,0,

%U 28649272821614715410221,14214363393075742724609375,7526219790642312236217153392,5968603205606800870499639536231

%N From Wendt's determinant compute sqrt(abs(A048954(n))/(2^n - 1)).

%C E. Lehmer claimed, and J. S. Frame proved, that a(n) is an integer (Ribenboim 1999, p. 128).

%C The subsequence for even n is A129205.

%C See A048954 for additional comments, references, links, and cross-references.

%D P. Ribenboim, Fermat's Last Theorem for Amateurs, Springer-Verlag, NY, 1999, pp. 126, 136.

%F a(n) = ((-1)^(n-1)*A048954(n)/(2^n - 1))^(1/2).

%t w[n_] := Resultant[x^n - 1, (1 + x)^n - 1, x]; Table[ Sqrt[Abs[w[n]]/(2^n - 1)], {n, 25}]

%Y Cf. A048954, A129205, A215616.

%K nonn

%O 1,3

%A _Jonathan Sondow_, Aug 17 2012