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 A321356 #26 Jan 10 2019 23:24:25 %S A321356 23,71,167,359,743,1511,12263,24551,196583,393191,786407,6291431, %T A321356 25165799,1610612711,6442450919,25769803751,103079215079,206158430183, %U A321356 6597069766631,864691128455135207,27670116110564327399,221360928884514619367,1770887431076116955111 %N A321356 Primes of the form 3*2^k - 25. %t A321356 Select[3*2^Range[4,100]-25 , PrimeQ] (* _Amiram Eldar_, Nov 15 2018 *) %o A321356 (PARI) for(n=0,20, if(ispseudoprime(p=3*2^n-25), print1(p, ", "))) %Y A321356 Cf. A050414, A321353 (k values). %K A321356 nonn %O A321356 1,1 %A A321356 _Gilbert Mozzo_, Nov 07 2018 %E A321356 More terms from _Amiram Eldar_, Nov 15 2018