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%I #17 Dec 06 2021 04:02:36
%S 4,283,50037,17650540,10405067904,9211817140115,11424093748466841,
%T 18896062057822100616,40192544399240309019728,
%U 106876212200059543898143707,347377340594805599176614321101
%N Sum of next n terms of the form i^i.
%C Sum of next n terms of the form i^n is A074209. Sum of first n terms of the form i^n is A031971. Sum of first n terms of the form i^i is A001923.
%H Seiichi Manyama, <a href="/A074309/b074309.txt">Table of n, a(n) for n = 1..193</a>
%F a(n) = Sum_{i=n+1..2n} i^i.
%F a(n) ~ (2*n)^(2*n). - _Vaclav Kotesovec_, Dec 06 2021
%e a(2) = 283 = 3^3 + 4^4, a(3) = 50037 = 4^4 + 5^5 + 6^6, a(4) = 17650540 = 5^5 + 6^6 + 7^7 + 8^8, a(5) = 10405067904 = 6^6 + 7^7 + 8^8 + 9^9 + 10^10.
%t Table[Sum[i^i, {i, n+1, 2n}], {n, 20}]
%o (PARI) a(n) = sum(k=n+1, 2*n, k^k); \\ _Seiichi Manyama_, Dec 05 2021
%Y Cf. A001923, A031971, A074209.
%K nonn
%O 1,1
%A _Zak Seidov_, Sep 22 2002
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