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A224840 Divisor sum of the arithmetic function A085945(n).

%I A224840 #31 Jan 21 2018 15:27:31
%S A224840 1,3,6,14,27,61,117,250,494,1012,2007,4088,8112,16357,32635,65493,
%T A224840 130779,262115,523710,1048502,2096110,4194124,8386419,16777182,
%U A224840 33550085,67108507,134209495,268434899,536853987,1073741664,2147449815,4294966187,8589868975,17179866799
%N A224840 Divisor sum of the arithmetic function A085945(n).
%C A224840 Also the number of subsets A of {1, 2, 3, ..., n} such that gcd(A) divides n.
%H A224840 Charles R Greathouse IV, <a href="/A224840/b224840.txt">Table of n, a(n) for n = 1..3321</a>
%H A224840 P. Pongsriiam, <a href="http://arxiv.org/abs/1306.4891">Relatively Prime Sets, Divisor Sums, and Partial Sums</a>, arXiv:1306.4891 and <a href="https://cs.uwaterloo.ca/journals/JIS/VOL16/Pongsriiam/pong2.html">J. Int. Seq. 16 (2013) #13.9.1</a>.
%H A224840 P. Pongsriiam, <a href="http://arxiv.org/abs/1306.2529">A remark on relative prime sets</a>, Integers 13 (2013), A49.
%F A224840 a(n) = sum{d | n} sum_{k <= d} mu(k)*(2^floor(n/k) - 1) where mu is the Moebius function.
%o A224840 (PARI) A085945(n)=sum(k=1, n, moebius(k)*(2^(n\k)-1))
%o A224840 a(n)=sumdiv(n,d,A085945(d)) \\ _Charles R Greathouse IV_, Sep 19 2013
%o A224840 (PARI) a(n)=my(v=vector(n,i,i));sum(i=1,2^n-1,n%gcd(vecextract(v,i))==0) \\ _Charles R Greathouse IV_, Sep 19 2013
%Y A224840 Cf. A038199, A027375, Divisor sums of A085945.
%K A224840 nonn
%O A224840 1,2
%A A224840 _Prapanpong Pongsriiam_, Sep 18 2013
%E A224840 a(19)-a(34) from _Charles R Greathouse IV_, Sep 19 2013