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Sum of the non-unitary divisors of A064115(n) (or of 1+A064115(n)).
2

%I #9 Jun 11 2019 00:10:24

%S 96,864,2160,5400,9600,6720,46080,94080,108864,191968,138240,345600,

%T 380160,482976,287280,806400,1016064,777600,1814400,3317760,3686400,

%U 3352320,5491200,5160960,3839400,5702400,4976640,7464960,7711200,8259840,10108800,12005760,10886400

%N Sum of the non-unitary divisors of A064115(n) (or of 1+A064115(n)).

%H Amiram Eldar, <a href="/A103846/b103846.txt">Table of n, a(n) for n = 1..344</a> (calculated from the b-file at A064115 by Giovanni Resta)

%e A103846(1)=96 is the sum of the non-unitary divisors of A064115(1)=188 and also of 1+A064115(1)=189: 2+94=96 and 3+9+21+63=96.

%t nusigma[1]=0; nusigma[n_] := DivisorSigma[1,n] - Times @@ (1 + Power @@@ FactorInteger[n]); seq={}; s1=0; Do[s2=nusigma[n]; If[s1>0 && s2==s1, AppendTo[seq, s1]]; s1=s2, {n,1,10^6}]; seq (* _Amiram Eldar_, Jun 10 2019 *)

%Y Cf. A048146, A064115.

%K nonn

%O 1,1

%A _Emeric Deutsch_, Feb 17 2005

%E More terms from _Amiram Eldar_, Jun 10 2019