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A127201 Base-2 logarithms of denominators corresponding to A127200. 1

%I

%S 2,1,3,5,6,6,4,7,8,11,12,11,13,14,15,17,18,18,18,16,19,23,24,25,26,27,

%T 28,26,29,31,32,33,34,35,36,36,35,37,38,41,42,41,43,44,45,47,48,49,50,

%U 51,52,52,52,52,46,53,54,59,60,58,61,62,63,64,65,67,68,69,70,70,68,73

%N Base-2 logarithms of denominators corresponding to A127200.

%t Table[Round[(1/Log[2])Log[Denominator[Sum[PrimePi[k]/2^k, {k, 2, x}]]]], {x, 2, 100}]

%o (PARI) a(n) = logint(denominator(sum(k=2, n, primepi(k)/2^k)), 2); \\ _Michel Marcus_, Oct 28 2019

%Y Cf. A119523, A127197, A127200.

%K nonn,frac

%O 2,1

%A _Artur Jasinski_, Jan 08 2007

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Last modified May 25 19:30 EDT 2020. Contains 334595 sequences. (Running on oeis4.)