OFFSET
1,2
COMMENTS
Concrete Mathematics Casino Problem - number of winners up to N.
REFERENCES
R. L. Graham, D. E. Knuth and O. Patashnik, Concrete Mathematics. 2nd Edition. Addison-Wesley, Reading, MA, 1994. Section 3.2, p74-76.
LINKS
Hugo Pfoertner, Table of n, a(n) for n = 1..10000
FORMULA
a(n)=floor(n/floor(n^(1/3)))+1/2*floor(n^(1/3))^2+5/2*floor(n^(1/3))-3
EXAMPLE
a(1000)=172
MATHEMATICA
Accumulate[Boole[Table[IntegerQ[n/Floor[n^(1/3)]], {n, 1, 73}]]] (* Geoffrey Critzer, May 25 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jan 30 2003
STATUS
approved