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%I #9 Jan 20 2024 17:57:26
%S 2,5,9,15,24,31,39,48,60,78,97,115,135,150,178,195,213,242,266,293,
%T 315,351,396,422,449,500,548,579,627,670,708,758,875,927,964,1003,
%U 1088,1140,1186,1229,1275,1351,1402,1535,1600,1737,1848,1913,1989,2051,2137,2204
%N a(n) = Sum_{i=1..n} A098168(i).
%F Conjecture: a(n)/triangular(n) -> Log(e*Pi/2).
%t NextPrime[n_Integer] := Block[{k}, k = n + 1; While[ !PrimeQ[k], k++ ]; k]; Fortunate[n_Integer] := Block[{p = Product[Prime[i], {i, 1, n}] + 1, q}, q = NextPrime[p]; q - p + 1]; t = Table[ PrimePi[ Fortunate[n]], {n, 70}]; Table[Plus @@ Take[t, n], {n, 52}] (* _Robert G. Wilson v_, Sep 04 2004 *)
%Y Cf. A005235, A055211, A098166, A098167, A098168.
%K nonn
%O 1,1
%A _Pierre CAMI_, Aug 30 2004
%E More terms from _Robert G. Wilson v_, Sep 04 2004