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%I #56 Aug 20 2021 15:09:45
%S 0,1,2,3,7,8,16,25,46,80,141,263,473,882,1628,3044,5734,10779,20428,
%T 38687,73653,140425,268340,513866,986033,1894409,3646134,7027825,
%U 13562625,26208248,50698865,98184467,190338061,369326690,717271793,1394198586,2712112561
%N Number of odd prime powers (A246655) between 2^n and 2^(n+1).
%H Ray Chandler, <a href="/A244508/b244508.txt">Table of n, a(n) for n = 0..91</a> (using b-file from A007053, corrected n = 45..52, n = 0..52 from Hiroaki Yamanouchi)
%F a(n) = A182908(n+1) - A182908(n). - _Ray Chandler_, Aug 20 2021
%e Between 2 and 4, there is just 1 prime power: 3, so a(1) = 1.
%e Between 4 and 8, there are 2 prime powers: 5 and 7, so a(2) = 2.
%t Table[Count[Range[2^n + 1, 2^(n + 1) - 1], _?PrimePowerQ], {n, 0, 27}] (* _Ivan N. Ianakiev_, Nov 18 2014 *)
%o (PARI) a(n) = sum(i=2^n+1, 2^(n+1)-1, isprimepower(i)>0);
%Y Cf. A246655 (prime powers), A182908 (positions of 2^n among prime powers).
%K nonn
%O 0,3
%A _Michel Marcus_, Nov 17 2014
%E a(28)-a(36) from _Hiroaki Yamanouchi_, Nov 20 2014
%E Minor edits by _Ray Chandler_, Aug 20 2021
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