%I #9 Dec 18 2019 02:01:47
%S 1,2,3,7,8,12,13,3138,3142,3146,3147,6272,6273,6277,6278,
%T 11112006825564294,11112006825564295,11112006825567420,
%U 11112006825567421,11112006825570546,11112006825570550
%N Cumulative sum of A000001(n)^A000001(n).
%C a(n) is prime for n = 2, 3, 4, 7, 14.
%C a(n) is semiprime for n = 9, 11, 18, 26.
%F a(n) = Sum_{i=1..n} A000001(i)^A000001(i).
%e a(7) = 1^1 + 1^1 + 1^1 + 2^2 + 1^1 + 2^2 + 1^1 = 13.
%e a(14) = 1^1 + 1^1 + 1^1 + 2^2 + 1^1 + 2^2 + 1^1 + 5^5 + 2^2 + 2^2 + 1^1 + 5^5 + 1^1 + 2^2 = 6277.
%e a(29) = 1^1 + 1^1 + 1^1 + 2^2 + 1^1 + 2^2 + 1^1 + 5^5 + 2^2 + 2^2 + 1^1 + 5^5 + 1^1 + 2^2 + 1^1 + 14^14 + 1^1 + 5^5 + 1^1 + 5^5 + 2^2 + 2^2 + 1^1 + 15^15 + 2^2 + 2^2 + 5^5 + 4^4 + 1^1 = 449005897206433320.
%Y Cf. A000001.
%K easy,nonn
%O 1,2
%A _Jonathan Vos Post_, Oct 13 2005
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