OFFSET
1,2
FORMULA
a(n) = (n/2)*(3n-1)+ n/sqrt(3) + O(1).
PROG
(PARI) a(n) = sum(i=1, n, floor(sqrt(3)*floor(sqrt(3)*i))); \\ Michel Marcus, Dec 05 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jun 13 2003
STATUS
approved