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A292598 a(n) is the number of odd primes in the sequence [n, floor(n/2), floor(n/4), ..., 1].

%I A292598 #9 Sep 27 2017 21:21:41
%S A292598 0,0,1,0,1,1,2,0,0,1,2,1,2,2,2,0,1,0,1,1,1,2,3,1,1,2,2,2,3,2,3,0,0,1,
%T A292598 1,0,1,1,1,1,2,1,2,2,2,3,4,1,1,1,1,2,3,2,2,2,2,3,4,2,3,3,3,0,0,0,1,1,
%U A292598 1,1,2,0,1,1,1,1,1,1,2,1,1,2,3,1,1,2,2,2,3,2,2,3,3,4,4,1,2,1,1,1,2,1,2,2,2
%N A292598 a(n) is the number of odd primes in the sequence [n, floor(n/2), floor(n/4), ..., 1].
%H A292598 Antti Karttunen, <a href="/A292598/b292598.txt">Table of n, a(n) for n = 1..16384</a>
%F A292598 a(1) = a(2) = 0; for n > 2, a(n) = A010051(n) + a(floor(n/2)).
%F A292598 a(n) = A000120(A292596(n)).
%F A292598 For all n >= 1, a(n) <= A078349(n).
%o A292598 (Scheme, with memoization-macro definec)
%o A292598 (definec (A292598 n) (if (<= n 2) 0 (+ (A010051 n) (A292598 (floor->exact (/ n 2))))))
%Y A292598 Cf. A010051, A065091, A078349, A292596.
%K A292598 nonn
%O A292598 1,7
%A A292598 _Antti Karttunen_, Sep 27 2017