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A350238 a(n) = Sum_{k=1..n} (-1)^(k+1) * floor((n/(2*k-1))^k).

%I A350238 #24 Dec 21 2021 21:11:47
%S A350238 1,2,2,3,4,3,3,4,4,4,3,4,6,4,3,4,6,4,3,6,5,5,6,5,7,4,4,4,5,3,6,5,5,6,
%T A350238 5,5,4,6,5,5,8,7,6,4,7,6,3,5,6,6,5,5,8,5,5,4,4,6,5,3,6,4,7,6,8,6,5,5,
%U A350238 7,6,4,4,7,4,5,9,8,5,6,6,8,7,3,6,6,7,7,4,9,10,3,8,4,7,6,8,10,6,4,11,7,7,5,7,11,6,8,8,9
%N A350238 a(n) = Sum_{k=1..n} (-1)^(k+1) * floor((n/(2*k-1))^k).
%C A350238 a(895) = -5.
%H A350238 Seiichi Manyama, <a href="/A350238/b350238.txt">Table of n, a(n) for n = 1..5000</a>
%e A350238 a(3) = [3/1] - [(3/3)^2] = 3 - 1 = 2.
%e A350238 a(4) = [4/1] - [(4/3)^2] = 4 - 1 = 3.
%e A350238 a(5) = [5/1] - [(5/3)^2] + [(5/5)^3] = 5 - 2 + 1 = 4.
%t A350238 a[n_] := Sum[(-1)^(k+1) * Floor[(n/(2*k-1))^k], {k, 1, n}]; Array[a, 100] (* _Amiram Eldar_, Dec 21 2021 *)
%o A350238 (PARI) a(n) = sum(k=1, (n+1)\2, (-1)^(k+1)*(n^k\(2*k-1)^k));
%Y A350238 Cf. A350147, A350167, A350223, A350239.
%K A350238 sign
%O A350238 1,2
%A A350238 _Seiichi Manyama_, Dec 21 2021