A066030 Card{i<=n, floor(n/i)=0 mod(i)}.

1, 1, 1, 2, 2, 1, 1, 2, 3, 2, 2, 2, 2, 1, 1, 3, 3, 3, 3, 3, 2, 1, 1, 2, 3, 2, 3, 4, 4, 1, 1, 3, 3, 2, 2, 4, 4, 3, 2, 3, 3, 1, 1, 2, 3, 2, 2, 3, 4, 4, 4, 4, 4, 4, 3, 3, 2, 1, 1, 2, 2, 1, 2, 5, 5, 3, 3, 3, 3, 2, 2, 4, 4, 3, 3, 4, 4, 2, 2, 3, 5, 4, 4, 3, 3, 2, 2, 3, 3, 2, 2, 3, 2, 1, 1, 3, 3, 3, 4, 6, 6, 4, 4, 5, 3

Offset

1,4

Links

Table of n, a(n) for n=1..105.

Formula

(1/n)*Sum_{i=1..n} a(i) = C*log(n)+O(log(n)) with C = 0.5...

Prog

(PARI) for(n=1, 150, print1(sum(i=1, n, if(floor(n/i)%i, 0, 1)), ", "))

Crossrefs

Sequence in context: A245424 A071784 A161638 * A025863 A346307 A339352

Adjacent sequences: A066027 A066028 A066029 * A066031 A066032 A066033

Keyword

nonn

Author

Benoit Cloitre, Dec 12 2001

Status

approved