OFFSET
1,6
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..5000
EXAMPLE
a(3) = [3/2] = 1.
a(4) = [4/2] - [(4/4)^2] = 2 - 1 = 1.
a(5) = [5/2] - [(5/4)^2] = 2 - 1 = 1.
MATHEMATICA
a[n_] := Sum[(-1)^(k + 1)*Floor[(n/(2*k))^k], {k, 1, n}]; Array[a, 100] (* Amiram Eldar, Dec 21 2021 *)
PROG
(PARI) a(n) = sum(k=1, n\2, (-1)^(k+1)*(n^k\(2*k)^k));
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Dec 21 2021
STATUS
approved