login
This site is supported by donations to The OEIS Foundation.

 

Logo

The submissions stack has been unacceptably high for several months now. Please voluntarily restrict your submissions and please help with the editing. (We don't want to have to impose further limits.)

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A137722 Number of numbers not greater than n with exactly one prime gap in their factorization. 3
0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 4, 5, 5, 5, 5, 6, 6, 7, 7, 7, 7, 7, 8, 9, 9, 9, 9, 10, 11, 12, 12, 13, 13, 14, 14, 15, 15, 15, 15, 16, 17, 18, 18, 18, 19, 20, 21, 22, 22, 22, 22, 23, 24, 24, 25, 26, 26, 27, 28, 29, 29, 29, 29, 30, 30, 31, 31, 32, 32, 33, 33, 34 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,14

COMMENTS

a(n) > a(n-1) iff A073490(n) = 1;

A137721(n) > a(n) for n < 134;

A137721(n) < a(n) for n > 140.

LINKS

R. Zumkeller, Table of n, a(n) for n = 1..1000

CROSSREFS

Cf. A073493.

Sequence in context: A103374 A208251 A241087 * A081305 A035665 A027388

Adjacent sequences:  A137719 A137720 A137721 * A137723 A137724 A137725

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Feb 09 2008

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified August 28 08:35 EDT 2015. Contains 261118 sequences.