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%I #9 Nov 23 2017 20:20:01
%S 0,1,1,1,1,3,1,1,1,3,1,4,1,3,3,1,1,4,1,4,3,3,1,5,1,3,1,4,1,7,1,1,3,3,
%T 3,5,1,3,3,5,1,7,1,4,4,3,1,6,1,4,3,4,1,5,3,5,3,3,1,10,1,3,4,1,3,7,1,4,
%U 3,7,1,6,1,3,4,4,3,7,1,6,1,3,1,10,3,3,3,5,1,10,3,4,3,3,3,7,1,4,4,5
%N a(1) = 0; thereafter, a(n) = number of divisors d of n such that if d = Product_(i) (p_i^e_i) then all e_i <= 1.
%C a(n) = number of non-powerful divisors d of n where powerful numbers are numbers from A001694(m) for m >=2.
%C Sequence is not the same as A183093(n): a(72) = 6, A183093(72) = 7.
%H Antti Karttunen, <a href="/A183093/b183093.txt">Table of n, a(n) for n = 1..16384</a>
%H <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>
%F a(n) = A000005(n) - A005361(n) = A183095(n) - 1.
%F a(1) = 0, a(p) = 1, a(pq) = 3, a(pq...z) = 2^k - 1, a(p^k) = 1, for p, q = primes, k = natural numbers, pq...z = product of k (k > 2) distinct primes p, q, ..., z.
%e For n = 12, set of such divisors is {2, 3, 6, 12}; a(12) = 4.
%o (Scheme) (define (A183093 n) (- (A000005 n) (A005361 n))) ;; _Antti Karttunen_, Nov 23 2017
%Y Cf. A000005, A005361, A183094, A183095, A183096.
%K nonn
%O 1,6
%A _Jaroslav Krizek_, Dec 25 2010