

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) = n1; 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: A355679 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. AdamsWatters, Nov 04 2009


STATUS

approved



