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.

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

Author

Amiram Eldar, Sep 07 2019

Keywords

• nonn

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)

Crossrefs

Cf. A033289, A033634, A268335, A325847.

Programs

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