A086214 - OEIS

%I #14 Jul 11 2024 01:23:51

%S 7,241,450283905890997361,36472996377170786401

%N Primes of the form 3^p-2 where p is prime.

%C Sum of reciprocals = 0.1470065204505038552417181957...

%C The next two terms, 3^317-2 and 3^541-2, are too large to include. - _Jorge Coveiro_, Apr 05 2004

%H Amiram Eldar, <a href="/A086214/b086214.txt">Table of n, a(n) for n = 1..6</a>

%t Select[3^#-2&/@Prime[Range[20]],PrimeQ] (* _Harvey P. Dale_, Sep 24 2022 *)

%o (PARI) xtopm1(n,k,r) = { sr=0; forprime(p=2,n, y=k^p-r; if(isprime(y),print1(y","); sr+=1./y; ); ); print(); print(sr) }

%Y Cf. A086218.

%K nonn

%O 1,1

%A _Cino Hilliard_, Aug 28 2003