OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
Stephan Ramon Garcia, Elvis Kahoro, Florian Luca, Primitive root discrepancy for twin primes, arXiv:1705.02485 [math.NT], 2017.
MATHEMATICA
s = {}; p = 3; Do[q = NextPrime[p]; If[q - p != 2, p = q; Continue[]]; If[EulerPhi[p + 1] > EulerPhi[p - 1], AppendTo[s, p]]; p = q, {15500}]; s (* Amiram Eldar, Sep 11 2019 *)
PROG
(PARI) lista(nn) = forprime(p=2, nn, if (isprime(p+2) && (eulerphi(p-1) < eulerphi(p+1)), print1(p, ", ")));
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Marcus, May 13 2017
STATUS
approved