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%I #14 May 06 2020 15:43:19
%S 1,1,2,37,71,2213,9596,1200305,24684613,287152493,1355849266,
%T 427675990237,1032458258547,228796942438201,16841089312342856,
%U 665478473553144001,1653031004194447737,631449646252135295657,3167496749732497119310
%N Numerator of (Sum(m^(n-1),m=1..n-1)+1)/n.
%D R. K. Guy, Unsolved Problems Number Theory, A17.
%H Indranil Ghosh, <a href="/A055031/b055031.txt">Table of n, a(n) for n = 1..200</a>
%t Table[Numerator[(Sum[m^(n - 1), {m, n - 1}] + 1)/n], {n, 50}] (* _Indranil Ghosh_, May 17 2017 *)
%o (PARI) a(n) = numerator((sum(m=1, n - 1, m^(n - 1)) + 1)/n); \\ _Indranil Ghosh_, May 17 2017
%o (Python)
%o from sympy import Integer
%o def a(n): return ((sum(m**(n - 1) for m in range(1, n)) + 1)/Integer(n)).numerator() # _Indranil Ghosh_, May 17 2017
%Y Cf. A055032, A055030, A055023, A201560, A204187.
%K nonn,frac
%O 1,3
%A _N. J. A. Sloane_, Jun 11 2000