%I A100447
%S A100447 2,4,8,20,60,188,632,2192,7712,27596,99880,364724,1342184,4971068,
%T A100447 18512792,69273668,260301176,981706832,3714566312,14096303344,
%U A100447 53634713552,204560302844,781874936816,2994414645860,11488774559636
%N A100447 Bisection of A000031.
%p A100447 with(numtheory):seq((1/(2*n+1))*add(phi(d)*2^((2*n+1)/d),d=divisors(2*n+1)),
               n=0..30); (C. Ronaldo)
%Y A100447 Cf. A000031, A100446. Equals 2*A026119.
%Y A100447 Sequence in context: A113180 A000116 A006407 this_sequence A112278 A059731 
               A001315
%Y A100447 Adjacent sequences: A100444 A100445 A100446 this_sequence A100448 A100449 
               A100450
%K A100447 nonn,easy
%O A100447 0,1
%A A100447 N. J. A. Sloane (njas(AT)research.att.com), Nov 21 2004
%E A100447 More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 19 2005