A348603 - OEIS

A348603

Larger 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).

204, 19332, 168730, 1099390, 1292570, 1598470, 2062570, 2429030, 3077354, 3903012, 4488910, 6135962, 5504110, 5812130, 7158710, 8221598, 9627915, 10893230, 10043690, 11049730, 10273670, 18087818, 19150222, 17578785, 23030090, 32174506, 35997346, 40117714, 39944086

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OFFSET

1,1

COMMENTS

The terms are ordered according to their smaller counterparts (A348602).

LINKS

Table of n, a(n) for n=1..29.

EXAMPLE

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

MATHEMATICA

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, m]], {n, 1, 1.7*10^6}]; seq

CROSSREFS

Cf. A160135, A348601, A348602.

Similar sequences: A002046, A002953, A126166, A126170, A259039, A292981, A322542, A324709, A348344.

Sequence in context: A099105 A253680 A209790 * A194192 A339199 A263505

Adjacent sequences: A348600 A348601 A348602 * A348604 A348605 A348606

KEYWORD

nonn

AUTHOR

Amiram Eldar, Oct 25 2021

STATUS

approved