

A225906


Indices of primes whose Wilson quotients are also prime.


3




OFFSET

1,1


COMMENTS

Is it a coincidence that the terms are alternately odd and even? Is it also a coincidence that the odd terms are all primes (= A225672)?


LINKS

Table of n, a(n) for n=1..7.
J. Sondow, Lerch Quotients, Lerch Primes, FermatWilson Quotients, and the WieferichnonWilson Primes 2, 3, 14771, in Proceedings of CANT 2011, arXiv:1110.3113
J. Sondow, Lerch Quotients, Lerch Primes, FermatWilson Quotients, and the WieferichnonWilson Primes 2, 3, 14771, Combinatorial and Additive Number Theory, CANT 2011 and 2012, Springer Proc. in Math. & Stat., vol. 101 (2014), pp. 243255.


FORMULA

a(n) = A000720(A050299(n+1)).


EXAMPLE

The Wilson quotient of 7 is ((71)!+1)/7 = 103, which is prime, and 7 is the 4th prime, so 4 is a member.


CROSSREFS

Cf. A000720, A007619, A050299, A122696, A225672.
Sequence in context: A123820 A261903 A133320 * A329524 A319067 A224503
Adjacent sequences: A225903 A225904 A225905 * A225907 A225908 A225909


KEYWORD

nonn


AUTHOR

Jonathan Sondow, May 20 2013


STATUS

approved



