Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A128216
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A128216 a(1)=a(2)=1. a(n+1) = a(n) + a(smallest prime dividing n). +0
2
1, 1, 2, 4, 5, 10, 11, 22, 23, 25, 26, 52, 53, 106, 107, 109, 110, 220, 221, 442, 443, 445, 446, 892, 893, 898, 899, 901, 902, 1804, 1805, 3610, 3611, 3613, 3614, 3619, 3620, 7240, 7241, 7243, 7244, 14488, 14489, 28978, 28979, 28981, 28982, 57964, 57965 (list; graph; listen)
OFFSET

1,3

LINKS

Leroy Quet, Home Page (listed in lieu of email address)

EXAMPLE

The smallest prime dividing 12 is 2. So a(13) = a(12) + a(2) = 52 + 1 = 53.

MAPLE

with(numtheory): a[1]:=1:a[2]:=1:for n from 2 to 55 do a[n+1]:=a[n]+a[factorset(n)[1]] od: seq(a[n], n=1..55); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 07 2007

CROSSREFS

Cf. A128215, A020639.

Sequence in context: A057762 A109511 A018339 this_sequence A080735 A091856 A083416

Adjacent sequences: A128213 A128214 A128215 this_sequence A128217 A128218 A128219

KEYWORD

nonn

AUTHOR

Leroy Quet Feb 19 2007

EXTENSIONS

More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 07 2007

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 25 20:09 EST 2009. Contains 167514 sequences.


AT&T Labs Research