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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
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
KEYWORD
nonn
AUTHOR
Amiram Eldar, Sep 07 2019
STATUS
approved