A129742 Numbers of the form: a(n)=((Prime[n] - 1)! - (Prime[n] - 1))/(2*Prime[n]).

0, 0, 2, 51, 164945, 18423138, 615376173176, 168483518571789, 24434798429947993043, 5256695596753687250025931034, 4278271932454694494134007741935

Offset

1,3

Comments

From the proof of Sir John Wilson's theorem:

numbers of sets of stellated p-gons.

References

G. E. Andrews, Number Theory, 1971, Dover Publications New York, p 39.

Links

Table of n, a(n) for n=1..11.

Formula

a(n)=((Prime[n] - 1)! - (Prime[n] - 1))/(2*Prime[n]).

Mathematica

f[n_] = ((Prime[n] - 1)! - (Prime[n] - 1))/(2*Prime[n]); Table[f[n], {n, 1, 20}]
((#-1)!-#+1)/(2#)&/@Prime[Range[20]] (* Harvey P. Dale, Aug 12 2016 *)

Crossrefs

Sequence in context: A099368 A132492 A030264 * A080921 A053455 A297947

Adjacent sequences: A129739 A129740 A129741 * A129743 A129744 A129745

Keyword

nonn

Author

Roger L. Bagula and Gary W. Adamson, Aug 25 2008

Status

approved