A166375 a(n) = sum (floor (j^2/n)) taken over 1 <= j <= n-1.

0, 1, 3, 4, 7, 11, 16, 20, 24, 31, 39, 44, 53, 63, 74, 80, 92, 103, 117, 128, 141, 157, 174, 186, 200, 219, 237, 252, 273, 293, 316, 332, 352, 377, 403, 420, 445, 473, 500, 520, 548, 575, 607, 634, 663, 695, 730, 756, 786, 819, 853, 884, 921, 959, 998

Offset: 2

Author

Christopher Hunt Gribble, Oct 13 2009

Keywords

• nonn

Links

• G. C. Greubel, Table of n, a(n) for n = 2..1000

Crossrefs

Row sums of A166373. Cf. A014817.

Programs

Maple

A166375 := proc(n)
    add( floor(j^2/n),j=1..n-1) ;
end proc: # R. J. Mathar, Jul 21 2015

Mathematica

Table[Sum[Floor[k^2/n], {k, 1, n - 1}], {n, 2, 100}] (* G. C. Greubel, May 10 2016 *)

PARI

a(n) = sum(j=1,n-1, j^2\n) \\ Michel Marcus, Jun 20 2013

Formula

a(n) = A014817(n) - n. - R. J. Mathar, Jul 21 2015