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%I #6 May 15 2019 14:09:51
%S 8,10,26,28,56,58,77,100,129,160,236,238,326,328,381,440,501,568,639,
%T 712,791,874,963,1060,1161,1264,1371,1480,1593,1720,1851,1988,2127,
%U 2276,2427,2584,2747,2914,3087,3266,3447,3638,3831,4028,4227,4438,4661,4888
%N Smallest composite number which is the sum of n consecutive prime numbers.
%F a(2n+1) = A007504(2n+1)
%F a(2n) = A007504(2n) if that value is composite, else A007504(2n+1) - 2.
%F a(n) ~ n^2 * log(n) / 2.
%e a(6) = 56 = 3 + 5 + 7 + 11 + 13 + 17. (2 + 3 + 5 + 7 + 11 + 13 is prime so not a member of this sequence.)
%t With[{prs=Prime[Range[500]]},Table[SelectFirst[Total/@Partition[ prs,n,1], CompositeQ],{n,2,50}]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, May 15 2019 *)
%K nonn
%O 2,1
%A _Claudio Meller_, Jun 22 2009