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%I #14 Apr 11 2022 17:25:34
%S 0,0,0,0,0,1,0,1,2,1,0,2,0,1,8,6,0,0,0,0,12,1,0,0,8,1,16,20,0,19,0,23,
%T 20,1,24,8,0,1,24,26,0,25,0,32,21,1,0,26,18,38,32,38,0,31,40,36,36,1,
%U 0,30,0,1,31,15,48,37,0,50,44,47,0,33,0,1,35,56
%N a(1) = a(2) = 0, for n>=3: (sum of non-divisors of n) modulo (number of non-divisors of n).
%C a(n) = 0 for n = 1, 2 and numbers from A140826.
%C a(n) = 1 for numbers of form 2*p (p=prime) from A100484 and other numbers, e.g. 8 and 13456 are only numbers n < 10^5 which are not of form 2*p with a(n) = 1.
%H Jaroslav Krizek, <a href="/A231167/b231167.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A024816(n) mod A049820(n).
%e For n=6, a(6) = A024816(6) mod A049820(6) = 9 mod 2 = 1.
%t ndn[n_]:=Module[{nd=Complement[Range[n],Divisors[n]]},Mod[Total[ nd],Length[ nd]]]; Join[{0,0},Array[ndn,80,3]] (* _Harvey P. Dale_, Apr 11 2022 *)
%Y Cf. A054025 (sigma(n) mod tau(n)), A024816, A049820, A024816, A049820, A065091, A230605, A161344.
%K nonn
%O 1,9
%A _Jaroslav Krizek_, Nov 07 2013
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