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A323069 Number of divisors d of n such that A049820(d) > 1 and A049820(d) is also a divisor of n.

%I A323069 #8 Jan 07 2019 11:13:18
%S A323069 0,0,0,0,0,1,0,1,0,0,0,2,0,0,1,1,0,2,0,0,0,0,0,3,0,0,0,0,0,3,0,1,0,0,
%T A323069 1,4,0,0,0,1,0,1,0,0,1,0,0,4,0,0,0,0,0,2,0,1,0,0,0,4,0,0,0,1,0,1,0,0,
%U A323069 0,2,0,5,0,0,1,0,0,1,0,1,0,0,0,2,0,0,0,1,0,4,0,0,0,0,0,4,0,0,1,0,0,1,0,1,2
%N A323069 Number of divisors d of n such that A049820(d) > 1 and A049820(d) is also a divisor of n.
%H A323069 Antti Karttunen, <a href="/A323069/b323069.txt">Table of n, a(n) for n = 1..10080</a>
%F A323069 Sum_{d|n} [A049820(d) > 1 and A049820(d)|n], where [ ] is the Iverson bracket.
%F A323069 a(n) <= A323068(n).
%F A323069 a(n) >= A322358(n).
%o A323069 (PARI) A323069(n) = sumdiv(n,d,my(t=(d-numdiv(d))); ((t>1)&&!(n%t)));
%Y A323069 Cf. A000005, A049820, A322358, A323068.
%K A323069 nonn
%O A323069 1,12
%A A323069 _Antti Karttunen_, Jan 05 2019