%I #3 Mar 30 2012 17:26:14
%S 1,2,3,5,4,6,7,9,8,11,10,12,13,15,14,17,16,19,21,18,23,25,20,22,24,27,
%T 29,26,28,31,33,30,35,32,37,34,39,41,36,43,38,45,40,42,47,49,51,53,44,
%U 46,55,48,57,50,59,52,61,54,56,63,58,65,67,60,62,69,64,71,66,68,73,75
%N Rearrangement of positive integers according to parity of (prime(n)-1)/2 (see comments).
%C If (prime(n+1)-1)/2 is even/odd then a(n) is the next even/odd number.
%t bb={};od=-1;ev=0;Do[If[EvenQ[(Prime[i]-1)/2], ev=ev+2;bb=Append[bb, ev], od=od+2;bb=Append[bb, od]], {i, 2, 200}];bb
%Y Cf. A105364.
%K nonn
%O 1,2
%A _Zak Seidov_, Apr 01 2005
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