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%I #10 Mar 12 2022 14:08:40
%S 2,3,7,13,19,43,53,97,103,109,127,139,173,181,193,229,241,257,263,283,
%T 307,313,349,397,409,421,457,463,487,499,509,563,593,643,653,691,709,
%U 769,787,811,823,829,853,859,877,883,907,919,937,947,967,977,1021,1051
%N Primes p such that neither the previous nor the next prime is of the form 6k+1.
%e 2 is a term because 3 is not a prime of the form 6k+1,
%e 3 is a term because 2 and 5 are not primes of the form 6k+1.
%e 7 is a term because 5 and 11 are not primes of the form 6k+1.
%o (PARI) lista(nn) = forprime(p=2, nn, if (((precprime(p-1) % 6) != 1) && ((nextprime(p+1) % 6) != 1), print1(p, ", "))); \\ _Michel Marcus_, Mar 12 2022
%Y Cf. A000040, A002476.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Dec 19 2009, Feb 11 2010
%E Entries checked by _R. J. Mathar_, Apr 14 2010
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