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%I #21 Aug 30 2018 11:43:15
%S 1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,
%T 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
%U 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3
%N Number of k, 1<=k<=n, such that k divides sigma(k).
%C a(n) is the number of multiply-perfect numbers (A007691) <= n. - _Robert Israel_, Aug 29 2018
%H Robert Israel, <a href="/A069926/b069926.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = Card(k: 1<=k<=n : sigma(k) == 0 (mod k) ).
%o (PARI) for(n=1,150,print1(sum(i=1,n,if(sigma(i)%(i),0,1)),","))
%Y Cf. A007691.
%K easy,nonn
%O 1,6
%A _Benoit Cloitre_, May 05 2002
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