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%I #4 Dec 05 2013 19:56:03
%S 1,8,311,40808,12185065,6287341056,4738802232119,5387114456064096,
%T 8850391860017878609,18339240151336533115830,
%U 44718225006409477834272143,173879507464360746581828003860
%N a(n) = numerator of the sum of the reciprocals of the n primes from prime(n(n-1)/2+1) to prime(n(n+1)/2).
%C Sum of all possible products of taking n-1 primes out of next n primes.
%t a[n_] := Numerator[Sum[1/Prime[i], {i, n(n-1)/2+1, n(n+1)/2}]]
%K nonn
%O 1,2
%A _Amarnath Murthy_, Apr 04 2003
%E More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 08 2003