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%I #19 Jul 09 2022 12:22:24
%S 5,7,11,19,31,47,79,103,191,239,383,479,863,991,2687,2879,3391,4799,
%T 6719,9343,21503,23039,36607,69119,72959,126719,152063,382463,602111,
%U 927743,972799,1096703,1102847,1640447,1655807,1966079,3565567,3590143,4124671,5402623
%N Primes p such that 2*p is a member of A230624.
%C It is not known if A230624 is infinite. Many of its initial terms are twice primes, so it would interesting if these primes could be characterized in some other way.
%C a(n)+1 typically has a slowly growing power of 2 as factor. as can be seen here: (PARI) for(k=1, #a, print1(valuation(a[k]+1,2),", ")): 1, 3, 2, 2, 5, 4, 4, 3, 6, 4, 7, 5, 5, 5, 7, 6, 6, 6, 6, 7, 10, 9, 8, 9, 8, 8, 9, 9, 12, 11, 11, 10, 10, 11, 10, 17, 11, 11, 12, 12,.. - _Hugo Pfoertner_ Jan 03 2022
%Y Cf. A230624, A349821.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Dec 30 2021
%E a(29)-a(40) from _Martin Ehrenstein_, Jan 03 2022
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