The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A105363 Rearrangement of positive integers according to parity of (prime(n)-1)/2 (see comments). 1

%I

%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

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

Last modified July 24 20:26 EDT 2021. Contains 346273 sequences. (Running on oeis4.)