A085727 Number of semiprimes between n and 2n (inclusive).

0, 1, 2, 2, 3, 3, 3, 4, 4, 3, 4, 4, 6, 6, 5, 4, 6, 7, 8, 9, 9, 8, 8, 8, 9, 9, 8, 9, 11, 11, 12, 12, 13, 12, 12, 11, 12, 12, 12, 11, 12, 12, 14, 15, 15, 16, 17, 18, 18, 17, 17, 16, 17, 17, 17, 17, 17, 17, 17, 18, 20, 21, 20, 20, 21, 20, 22, 22, 22, 21, 23, 24, 26, 26, 25, 25, 25, 25, 26

Offset

1,3

Links

Table of n, a(n) for n=1..79.

Crossrefs

Sequence in context: A072644 A179864 A070082 * A343005 A143442 A137300

Adjacent sequences: A085724 A085725 A085726 * A085728 A085729 A085730

Keyword

easy,nonn

Author

Jason Earls, Jul 20 2003

Status

approved