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 A093433 #15 Apr 13 2024 22:20:09 %S A093433 2,5,41,1031,46399,2803043,247140857,25627356863,3359824134707, %T A093433 525738142728791,86239154183764823,16043263583368582931, %U A093433 3203015861712721419161,765364544804215147351277,196164712685969109811322179,51407675872783850510756055649 %N A093433 a(n) = (p(1)*...*p(n)) + (p(n+1)*...*p(2n)) where p(n) is the n-th prime. %F A093433 a(n) = A002110(n) + A107712(n). %e A093433 a(5) = 2803043 because 2*3*5*7*11 + 13*17*19*23*29 = 2803043. %p A093433 a:= n-> add(mul(ithprime(i+j), i=1..n), j=[0, n]): %p A093433 seq(a(n), n=0..20); # _Alois P. Heinz_, Apr 13 2024 %Y A093433 Cf. A000040, A002110, A107712. %K A093433 easy,nonn %O A093433 0,1 %A A093433 _Jason Earls_, May 12 2004