login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Primes p such that W_p == 2 (mod p), where W_p = A007619(n) and p = prime(n).
0

%I #13 Jan 24 2021 14:56:19

%S 19,1187,14296621,16556218163369

%N Primes p such that W_p == 2 (mod p), where W_p = A007619(n) and p = prime(n).

%C These are the members of René Gy's set W_2 (cf. Gy, 2018).

%C The sequence is complete to 2*10^13, with the higher terms coming from a list of primes with small Wilson quotients in the article by Costa, Gerbicz, and Harvey. - _John Blythe Dobson_, Jan 05 2021

%H Edgar Costa, Robert Gerbicz, and David Harvey, <a href="https://doi.org/10.1090/S0025-5718-2014-02800-7">A search for Wilson primes</a>, Mathematics of Computation 83 (2014) 3071-3091.

%H R. Gy, <a href="http://math.colgate.edu/~integers/s10/s10.mail.html">Generalized Lerch Primes</a>, Integers: Electronic Journal of Combinatorial Number Theory 18, (2018), #A10.

%o (PARI) forprime(p=1, , if(Mod(((p-1)!+1)/p, p)==2, print1(p, ", ")))

%Y Cf. A007540, A197632.

%K nonn,hard,more

%O 1,1

%A _Felix Fröhlich_, Sep 08 2018