A348602 - OEIS

%I #7 Oct 25 2021 11:11:39

%S 198,18180,142310,1077890,1156870,1511930,1669910,2236570,2728726,

%T 3776580,4246130,4532710,5123090,5385310,6993610,7288930,8619765,

%U 8754130,8826070,9478910,10254970,14426230,17041010,17257695,21448630,30724694,34256222,35361326,37784810

%N Smaller member of a nonexponential amicable pair: numbers (k, m) such that nesigma(k) = m and nesigma(m) = k, where nesigma(k) is the sum of the nonexponential divisors of k (A160135).

%C The larger counterparts are in A348603.

%e 198 is a term since A160135(198) = 204 and A160135(204) = 198.

%t esigma[n_] := Times @@ (Sum[First[#]^d, {d, Divisors[Last[#]]}] &) /@ FactorInteger[n]; s[n_] := DivisorSigma[1, n] - esigma[n]; seq = {}; Do[m = s[n]; If[m > n && s[m] == n, AppendTo[seq, n]], {n, 1, 1.7*10^6}]; seq

%Y Cf. A160135, A348601, A348603.

%Y Similar sequences: A002025, A002952, A126165, A126169, A259038, A292980, A322541, A324708, A348343.

%K nonn

%O 1,1

%A _Amiram Eldar_, Oct 25 2021