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%I #7 Dec 03 2016 12:06:26
%S 0,1,5,139,35692,111565148,5205269945088,4286767657466006784,
%T 71920030250887607243833344,27863293344390107424172413346185216,
%U 278632933465479015464665989671020186828800000,79497227734495207011816776516244120065118266248396800000
%N a(n) = unreduced numerator in Sum_{k=1..n}(1/k^k).
%H Daniel Suteu, <a href="/A279017/b279017.txt">Table of n, a(n) for n = 0..19</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Sophomore's_dream">Sophomore's dream</a>.
%F a(n) ~ A073009 * A002109(n).
%F a(0) = 0, a(n) = n^n * a(n-1) + A002109(n-1).
%o (PARI) sum(k=1, n, 1/k^k) * prod(k=1, n, k^k)
%Y Cf. A073009.
%K nonn,easy
%O 0,3
%A _Daniel Suteu_, Dec 03 2016