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%I #8 Mar 21 2021 13:05:46
%S 0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,2,2,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,
%T 4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,6,6,6,6,6,6,6,6,6,6,7,7,7,
%U 7,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,9,10,10,10,10,10,10,10,10,10,10
%N Number of numbers <= n having only one abundant divisor (A091191).
%H Amiram Eldar, <a href="/A091195/b091195.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/AbundantNumber.html">Abundant Number</a>.
%t f[n_] := Boole[Count[Divisors[n], _?(DivisorSigma[1, #] > 2 # &)] == 1]; Accumulate @ Array[f, 100] (* _Amiram Eldar_, Mar 21 2021 *)
%Y Partial sums of A294930.
%Y Cf. A091191, A091194, A005101.
%K nonn
%O 1,18
%A _Reinhard Zumkeller_, Dec 27 2003
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