%I #6 Apr 27 2019 02:03:31

%S 0,1,2,6,3,7,4,8,5,9,10,26,11,27,12,28,13,29,14,30,15,31,16,32,17,33,

%T 18,34,19,35,20,36,21,37,22,38,23,39,24,40,25,41,42,106,43,107,44,108,

%U 45,109,46,110,47,111,48,112,49,113,50,114,51,115,52,116,53,117,54,118,55,119,56,120,57,121,58,122,59

%N a(n) = (A132207(n)-1)/3.

%p A132207 := proc(n)

%p L := [] ;

%p for k from 0 to (2*4^n-1)/2 do

%p L := [op(L),2*4^n+3*k-1,5*4^n+3*k-1] ;

%p end do:

%p end proc:

%p for n from 0 to 3 do

%p L := A132207(n) ;

%p for l in L do

%p printf("%d,",(l-1)/3) ;

%p end do:

%p end do:

%p # _R. J. Mathar_, Sep 26 2011

%Y Cf. A132207.

%K easy,nonn

%O 0,3

%A _Omar E. Pol_, Jan 05 2009