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A215615 From Wendt's determinant compute sqrt(abs(A048954(n))/(2^n - 1)). 5
1, 1, 2, 5, 11, 0, 232, 2295, 26714, 453871, 7053157, 0, 7715707299, 545539395584, 42297694603648, 4883188189089105, 531361846217471443, 0, 28649272821614715410221, 14214363393075742724609375, 7526219790642312236217153392, 5968603205606800870499639536231 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

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

The subsequence for even n is A129205.

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

REFERENCES

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

LINKS

Table of n, a(n) for n=1..22.

FORMULA

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

MATHEMATICA

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

CROSSREFS

Cf. A048954, A129205, A215616.

Sequence in context: A133035 A133516 A163784 * A018862 A175310 A175311

Adjacent sequences:  A215612 A215613 A215614 * A215616 A215617 A215618

KEYWORD

nonn

AUTHOR

Jonathan Sondow, Aug 17 2012

STATUS

approved

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Last modified October 20 17:39 EDT 2017. Contains 293648 sequences.