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A163211 Swinging Wilson quotients (A163210) which are primes. 3
3, 23, 71, 757, 30671, 1383331, 245273927, 3362110459, 107752663194272623, 5117886516250502670227, 34633371587745726679416744736000996167729085703, 114326045625240879227044995173712991937709388241980425799 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(14)-a(18) certified prime by Primo 4.2.0. a(17) = A163210(569) = P1239, a(18) = A163210(787) = P1812. - Charles R Greathouse IV, Dec 11 2016
LINKS
Peter Luschny, Swinging Primes.
EXAMPLE
The quotient (252+1)/11 = 23 is a swinging Wilson quotient and a prime, so 23 is a member.
MAPLE
A163211 := n -> select(isprime, A163210(n));
MATHEMATICA
sf[n_] := n!/Quotient[n, 2]!^2; a[n_] := (p = Prime[n]; (sf[p - 1] + (-1)^Floor[(p + 2)/2])/p); Select[PrimeQ][Table[a[n], {n, 1, 100}]] (* G. C. Greubel, Dec 10 2016 *)
PROG
(PARI) sf(n)=n!/(n\2)!^2
forprime(p=2, 1e3, t=sf(p-1)\/p; if(isprime(t), print1(t", "))) \\ Charles R Greathouse IV, Dec 11 2016
CROSSREFS
Sequence in context: A107177 A096207 A163210 * A126335 A256329 A196649
KEYWORD
nonn
AUTHOR
Peter Luschny, Jul 24 2009
STATUS
approved

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Last modified February 26 07:39 EST 2024. Contains 370335 sequences. (Running on oeis4.)