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A325848 Larger of exponentially-odd amicable numbers pair: numbers m < k such that m = s(k) and k = s(m), where s(k) is the sum of proper exponential-odd divisors of k. 2
378, 4584, 16632, 16728, 64032, 76704, 179118, 168730, 225096, 256338, 266568, 391656, 401952, 387720, 393528, 593952, 788448, 781728, 897888, 1052088, 1099390, 1292570, 1346598, 1598470, 2062570, 1863918, 2099424, 1940856, 2223720, 2429030, 2980056, 3336984 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The terms are ordered according to their lesser counterparts (A325847).

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..789 (terms with lesser counterparts below 10^10)

MATHEMATICA

f[e_] := If[OddQ[e], e + 2, e + 1]; fun[p_, e_] := 1 + (p^f[e] - p)/(p^2 - 1); a[1] = 1; a[n_] := Times @@ (fun @@@ (fct = FactorInteger[n])) - If[AllTrue[fct[[;; , 2]], OddQ], n, 0]; s = {}; Do[m = a[n]; If[m > n && a[m] == n, AppendTo[s, m]], {n, 1, 10^5}]; s

CROSSREFS

Cf. A033289, A033634, A268335, A325847.

Sequence in context: A047632 A033699 A235544 * A248915 A225839 A221803

Adjacent sequences:  A325845 A325846 A325847 * A325849 A325850 A325851

KEYWORD

nonn

AUTHOR

Amiram Eldar, Sep 07 2019

STATUS

approved

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Last modified February 27 03:02 EST 2020. Contains 332299 sequences. (Running on oeis4.)