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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A234999 Primes p such that the p-th evil number is prime; 2 together with evil primes p such that 2p - 1 is prime.

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%I A234999 #12 May 21 2025 16:41:58
%S A234999 2,3,139,337,547,619,691,811,937,1237,1297,1399,1429,2089,2179,2221,
%T A234999 2281,2467,2539,2617,2707,2719,2791,2851,3019,3067,3499,3739,3769,
%U A234999 4027,4177,4357,4447,4567,4951,5431,5479,5557,5581,5749,6037,6229,6379,6421,6691,6841,7507
%N A234999 Primes p such that the p-th evil number is prime; 2 together with evil primes p such that 2p - 1 is prime.
%C A234999 This sequence is the intersection of A005382 and A027699.
%H A234999 Charles R Greathouse IV, <a href="/A234999/b234999.txt">Table of n, a(n) for n = 1..10000</a>
%e A234999 2 is a prime and A001969(2) = 3, a prime also, thus 2 is in this sequence; 3 is a prime and A001969(3) = 5, a prime also, thus 3 is in this sequence; 139 is a prime A001969(139) = 277, a prime also, thus 139 is this sequence.
%o A234999 (PARI) is(n)=isprime(n) && isprime(2*n--+hammingweight(n)%2) \\ _Charles R Greathouse IV_, Jan 02 2014
%Y A234999 Cf. A057738, A232667.
%K A234999 nonn
%O A234999 1,1
%A A234999 _Antti Karttunen_ and _Juri-Stepan Gerasimov_, Jan 02 2014
%E A234999 a(28) inserted by _Charles R Greathouse IV_, Jan 02 2014