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.
%I A117587 #12 Feb 02 2019 18:46:54 %S A117587 3,4,7,8,16,23,49,89,331,497,1122,11222 %N A117587 Numbers k such that 2^prime(k) - prime(k)^2 is prime. %C A117587 No more terms below 5000. - _Giovanni Resta_, Apr 03 2006 %C A117587 p is a prime element of the sequence A072180 iff pi(p) is a term of A117587. So since 119087 is a prime term of A072180, pi(119087)= 11222 is in the sequence. - _Farideh Firoozbakht_, Dec 08 2006 %e A117587 4 is in the sequence because the 4th prime is 7 and 2^7 - 7^2 = 79 is a prime. %p A117587 a:=proc(n) if isprime(2^ithprime(n)-ithprime(n)^2) then n else fi end: seq(a(n),n=1..400); # _Emeric Deutsch_, Apr 06 2006 %t A117587 Select[Range[1200], PrimeQ[2^# - #^2] &@ Prime@ # &] (* _Michael De Vlieger_, Feb 02 2019 *) %o A117587 (PARI) for(i=1,100,if(isprime(2^prime(i)-prime(i)^2),print1(i,","))) %Y A117587 Cf. A072180. %K A117587 hard,more,nonn %O A117587 1,1 %A A117587 Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), Apr 03 2006 %E A117587 3 more terms from _Giovanni Resta_, Apr 03 2006 %E A117587 One more term from _Farideh Firoozbakht_, Dec 08 2006