%I
%S 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,
%T 27,29,28,31,30,32,33,34,35,37,36,38,39,41,40,44,43,45,47,46,48,49,50,
%U 51,53,52,54,55,56,57,59,58,61,60,62,63,65,65,67,66,68,69,71,70,73,72
%N Exchange adjacent nonprimes and primes.
%C 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".
%Y Cf. A014681
%K easy,nonn
%O 1,1
%A _Giovanni Teofilatto_, Nov 03 2009
%E Edited by Franklin T. AdamsWatters, Nov 04 2009
