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%I #8 May 10 2014 17:12:56
%S 37,265717,193710241,1270932914161,
%T 187855106306818130162790081799568953899918191769361,
%U 884821727139988111281341588371104523273965529248966451172919369920848760385637
%N Primes p such that 2p+7 is a power of three.
%C If (3^i-7)/2 is prime then x=3^i-7 is a solution of sigma(x)+7 = sigma(x+7). See A063680 and indices resulting in primes are in A063679.
%C The next term (a(7)) has 118 digits. - _Harvey P. Dale_, May 10 2014
%F 2*37+7 = 3^4, so 37 is in the sequence.
%t Select[(#-7)/2&/@(3^Range[2,250]),PrimeQ] (* _Harvey P. Dale_, May 10 2014 *)
%Y Cf. A063679, A063680.
%K nonn
%O 1,1
%A _Jud McCranie_, Jul 29 2001
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