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%I #28 Oct 27 2023 22:00:46
%S 0,1,0,1,0,0,0,3,1,2,0,4,0,0,0,1,0,3,0,0,0,0,0,4,1,2,0,2,0,0,0,3,0,2,
%T 0,1,0,0,0,2,0,0,0,0,0,0,0,4,0,3,0,2,0,0,0,0,0,2,0,0,0,0,2,1,0,0,0,0,
%U 0,0,0,3,0,2,4,2,0,0,0,6,1,2,0,8,0,0,0,4,0,6,0,0,0,0,0,0,0,3,0,1,0,0,0,2,0
%N Sum of divisors of n read modulo (number of divisors of n).
%C a(A003601(n)) = 0; a(A049642(n)) > 0. [_Reinhard Zumkeller_, Jan 06 2012]
%H Reinhard Zumkeller, <a href="/A054025/b054025.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A000203(n) mod A000005(n), sigma(n) mod tau(n).
%p with(numtheory): seq(sigma(i) mod tau(i),i=1..120);
%t Table[Mod[DivisorSigma[1,n],DivisorSigma[0,n]],{n,110}] (* _Harvey P. Dale_, Nov 16 2011 *)
%o (Haskell)
%o import Data.List (genericIndex)
%o a054025 n = genericIndex a054025_list (n-1)
%o a054025_list = zipWith mod a000203_list a000005_list
%o -- _Reinhard Zumkeller_, Jul 28 2014, Jan 06 2012
%o (PARI) vector(90, n, sigma(n) % numdiv(n)) \\ _Michel Marcus_, Aug 15 2015
%Y Cf. A000005, A000203.
%Y Cf. A003601, A049642, A245656.
%K nonn
%O 1,8
%A _Asher Auel_, Jan 19 2000
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