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

 

Logo

Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A167419 Exchange adjacent nonprimes and primes. 0
2, 1, 4, 3, 6, 5, 8, 7, 9, 11, 10, 13, 12, 14, 15, 17, 16, 19, 18, 20, 21, 23, 22, 24, 25, 26, 27, 29, 28, 31, 30, 32, 33, 34, 35, 37, 36, 38, 39, 41, 40, 44, 43, 45, 47, 46, 48, 49, 50, 51, 53, 52, 54, 55, 56, 57, 59, 58, 61, 60, 62, 63, 65, 65, 67, 66, 68, 69, 71, 70, 73, 72 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

If we have consecutive numbers, one prime and one nonprime, swap them. So after the initial 2,1,4,3,6,5,8,7 we have "if n is prime, a(n) = n-1; if n+1 is prime, a(n) = n+1, otherwise a(n) = n".

LINKS

Table of n, a(n) for n=1..72.

CROSSREFS

Cf. A014681

Sequence in context: A076981 A147965 A167542 * A114285 A014681 A103889

Adjacent sequences:  A167416 A167417 A167418 * A167420 A167421 A167422

KEYWORD

easy,nonn

AUTHOR

Giovanni Teofilatto, Nov 03 2009

EXTENSIONS

Edited by Franklin T. Adams-Watters, Nov 04 2009

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy .

Last modified November 20 10:41 EST 2017. Contains 294963 sequences.