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 A165657 #4 Jul 17 2015 10:52:15 %S A165657 2,3,15,105,385,5005,17017,323323,1062347,30808063,434113615, %T A165657 35336848261,1448810778701,33545541876077,266186053068611, %U A165657 5426100312552455,9156001667401012567,42962777054727828199 %N A165657 Numerators of A002110 divided by A102647, starting from the second term of both. %o A165657 (PARI) a1(n)=prod(i=1, n, prime(i)); b1(n)=prod(i=1, n, prime(n+1)%prime(i)); %o A165657 a(n)=if(n<0, 0, numerator(a1(n)/b1(n))); for(n=1, 20, print1(a(n) ", ")) %Y A165657 Cf. A002110, A102647, A165658, A165659, A165660. %K A165657 easy,nonn %O A165657 1,1 %A A165657 _Creighton Dement_, Sep 24 2009