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%I #4 Mar 30 2012 18:36:32
%S 0,0,0,1,1,1,3,3,3,4,4,4,7,7,7,8,8,8,10,10,10,11,11,11,15,15,15,16,16,
%T 16,18,18,18,19,19,19,22,22,22,23,23,23,25,25,25,26,26,26,31,31,31,32,
%U 32,32,34,34,34,35,35,35,38,38,38,39,39,39,41,41,41,42,42,42
%N Factors of 2 in the denominators of the fractional coefficients of the square-root of the prime power series: sum_{n=0..inf} p_n x^n, where p_n is the n-th prime and p_0 is defined to be 1.
%C Are all the denominators exact powers of 2?
%F Convolution of sum_{n=0..inf} A073749(n)/[D_n*2^{a(n)}] x^n yields the prime power series sum_{n=0..inf} p_n x^n, where p_n is the n-th prime and p_0=1 and where D_n is a positive integer; D_n for the first 60 terms is 1 (is it always equal to 1?).
%Y Cf. A073749.
%K easy,frac,nonn
%O 0,7
%A _Paul D. Hanna_, Aug 07 2002