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a(n) = sum of next a(n-1) primes after a(n-1) with a(1) = 1.
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%I #11 Mar 04 2013 17:50:03

%S 1,2,8,180,135602,140706863394

%N a(n) = sum of next a(n-1) primes after a(n-1) with a(1) = 1.

%e a(1) = 1, a(2) = 2, a(3) = 3 + 5 = 8, a(4) = 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37 = 180.

%t NestList[Sum[Prime[i], {i, (b = PrimePi[#] + 1), b + # - 1}] &, 1, 5]

%K nonn,more

%O 1,2

%A _Zak Seidov_, Mar 01 2013