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 A097590 #14 Dec 18 2019 04:05:59 %S A097590 3,10,21,34,51,80,103,146,187,260,319,366,455,522,595,702,791,892, %T A097590 1019,1116,1199,1288,1385,1636,1767,1880,2031,2294,2545,2768,2947, %U A097590 3336,3617,3768,3965,4138,4377,4610,4801,5024,5247,5540,6133,6426,6883,7110,7421 %N A097590 a(n) = Sum_{i=2..n} A055211(i). %F A097590 Let F(n) := a(n)/A007504(n). Conjecture: as n tends to infinity F(n) tends to Pi/2 with Pi=3.14159...... %t A097590 PrevPrime[ n_Integer] := Block[ {k = n - 1}, While[ ! PrimeQ[ k ], k-- ]; k ]; LF[ n_Integer ] := Block[ { p = Product[ Prime[ i ], {i, 1, n} ] - 1, q}, q = PrevPrime[ p ]; p - q + 1 ]; t = Table[LF[ n ], {n, 2, 48}]; Table[Plus @@ Take[t, n], {n, 47}] (* _Robert G. Wilson v_, Sep 04 2004 *) %Y A097590 Cf. A007504, A055211. %K A097590 nonn %O A097590 2,1 %A A097590 _Pierre CAMI_, Aug 29 2004 %E A097590 More terms from _Robert G. Wilson v_, Sep 04 2004