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%I #13 Feb 22 2021 14:25:30
%S 0,0,0,0,0,1,0,0,0,0,0,2,0,0,0,0,0,2,0,1,0,0,0,3,0,0,0,1,0,2,0,0,0,0,
%T 0,4,0,0,0,2,0,2,0,0,0,0,0,4,0,0,0,0,0,3,0,2,0,0,0,5,0,0,0,0,0,2,0,0,
%U 0,1,0,6,0,0,0,0,0,2,0,3,0,0,0,5,0,0,0,1,0,4,0,0,0,0,0,5,0,0,0,2,0,2,0,1,0,0,0,6,0,0,0,3,0,2,0,0,0,0,0,8
%N Number of nondeficient divisors of n.
%C Number of nondeficient numbers (A023196) dividing n.
%H Antti Karttunen, <a href="/A341620/b341620.txt">Table of n, a(n) for n = 1..65537</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F a(n) = Sum_{d|n} A294936(d).
%F a(n) = A294927(n) + A294936(n).
%F a(n) = A080224(n) + A080225(n) = A000005(n) - A080226(n).
%F a(n) >= A337690(n) for all n.
%F a(n) = 1 iff A341619(n) = 1.
%t a[n_] := DivisorSum[n, 1 &, DivisorSigma[1, #] >= 2*# &]; Array[a, 120] (* _Amiram Eldar_, Feb 22 2021 *)
%o (PARI)
%o A294936(n) = (sigma(n, -1)>=2); \\ From A294936.
%o A341620(n) = sumdiv(n,d,A294936(d));
%o (PARI) A341620(n) = sumdiv(n,d,(sigma(d)>=(2*d)));
%Y Cf. A000005, A006039 (positions of ones), A023196, A080224, A080225, A080226, A294927, A294936, A337690, A341619.
%Y Differs from a derived sequence A341624 for the first time at n=120, where a(120)=8, while A341624(120)=1.
%K nonn
%O 1,12
%A _Antti Karttunen_, Feb 21 2021
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