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 A074382 #12 Aug 30 2019 14:10:15
%S A074382 1,2,6,4,2,6,2,12,12,12,30,18,24,10,14,32,22,12,14,10,6,12,30,44,40,
%T A074382 54,28,8,24,26,6,8,28,48,12,158,20
%N A074382 Difference between (1+3^n)-th and (3^n)-th primes.
%F A074382 a(n) = prime(1+3^n) - prime(3^n).
%e A074382 n=25: a(25)=54 because the 847288609443rd prime is 25270000074757 and the 847288609444th prime is 25270000074811.
%t A074382 NextPrime[#]-#&/@Table[Prime[3^n],{n,25}] (* _Harvey P. Dale_, Sep 29 2015 *)
%Y A074382 Cf. A074325, A038833.
%K A074382 hard,more,nonn
%O A074382 0,2
%A A074382 _Labos Elemer_, Aug 22 2002
%E A074382 Corrected by _Harvey P. Dale_, Sep 29 2015
%E A074382 a(0), a(26)-a(36) from _Chai Wah Wu_, Aug 30 2019