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 A323758 Lesser of modified exponential amicable pairs. 2
 114, 366, 1140, 3660, 3864, 5016, 11040, 16104, 16536, 44772, 57960, 67158, 68640, 142290, 142310, 180960, 196248, 198990, 240312, 248040, 308220, 322080, 326424, 339822, 348840, 352632, 366792, 462330, 669900, 671580, 785148, 815100, 817440, 849240, 912072 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A modified exponential amicable pair (m, n) has A241405(m) = A241405(n) = m + n + 1. The larger counterparts are in A323759. LINKS Amiram Eldar, Table of n, a(n) for n = 1..4725 (terms below 2*10^11) David Moews, Perfect, amicable and sociable numbers. MATHEMATICA 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 PROG (PARI) f(n) = {my(f=factor(n)); prod(i=1, #f[, 1], sumdiv(f[i, 2]+1, d, f[i, 1]^(d-1))); } \\ A241405 fm(n) = f(n) - n; isok(n) = my(fn=fm(n)); (fn > n) && (fm(fn) == n); \\ Michel Marcus, Jan 30 2019 CROSSREFS Cf. A241405, A323757, A323759. Sequence in context: A300478 A305066 A322541 * A043403 A122279 A251481 Adjacent sequences:  A323755 A323756 A323757 * A323759 A323760 A323761 KEYWORD nonn AUTHOR Amiram Eldar, Jan 26 2019 STATUS approved

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Last modified June 20 19:36 EDT 2019. Contains 324234 sequences. (Running on oeis4.)