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%I #16 Feb 18 2019 05:30:06
%S 114,366,1140,3660,3864,5016,11040,16104,16536,44772,57960,67158,
%T 68640,142290,142310,180960,196248,198990,240312,248040,308220,322080,
%U 326424,339822,348840,352632,366792,462330,669900,671580,785148,815100,817440,849240,912072
%N Lesser of modified exponential amicable pairs.
%C A modified exponential amicable pair (m, n) has A241405(m) = A241405(n) = m + n + 1.
%C The larger counterparts are in A323759.
%H Amiram Eldar, <a href="/A323758/b323758.txt">Table of n, a(n) for n = 1..4725</a> (terms below 2*10^11)
%H David Moews, <a href="http://djm.cc/amicable.html">Perfect, amicable and sociable numbers</a>.
%t f[p_, e_] := DivisorSum[e+1, p^(#-1)&]; mesigma[1]=1; mesigma[n_] := Times @@ f @@@FactorInteger@ n; s={}; mes[n_] := mesigma[n]-n; Do[m=mes[n]; If[m>n && mes[m]==n, AppendTo[s, n]], {n,1,10000}]; s
%o (PARI) f(n) = {my(f=factor(n)); prod(i=1, #f[, 1], sumdiv(f[i, 2]+1, d, f[i, 1]^(d-1)));} \\ A241405
%o fm(n) = f(n) - n;
%o isok(n) = my(fn=fm(n)); (fn > n) && (fm(fn) == n); \\ _Michel Marcus_, Jan 30 2019
%Y Cf. A241405, A323757, A323759.
%K nonn
%O 1,1
%A _Amiram Eldar_, Jan 26 2019
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