login
A131703
a(n) = Sum_{k=1..floor(sqrt(n))} floor(k*sqrt(n)).
0
1, 1, 1, 6, 6, 6, 7, 7, 18, 18, 18, 19, 20, 21, 21, 40, 40, 40, 42, 42, 44, 45, 46, 46, 75, 75, 75, 77, 78, 79, 81, 82, 83, 85, 85, 126, 126, 126, 128, 129, 132, 132, 135, 136, 138, 139, 141, 141, 196, 196, 196, 199, 200, 203, 204, 205, 208, 210, 212, 213, 215, 217, 217
OFFSET
1,4
MATHEMATICA
Table[Sum[Floor[k*Sqrt[n]], {k, 1, Floor[Sqrt[n]]}], {n, 1, 75}] (* Stefan Steinerberger, Sep 18 2007 *)
CROSSREFS
Sequence in context: A195504 A098537 A276861 * A352764 A329087 A135357
KEYWORD
nonn
AUTHOR
Leroy Quet, Sep 16 2007
EXTENSIONS
More terms from Stefan Steinerberger, Sep 18 2007
STATUS
approved