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Maximal elements of pairs of "Super Unitary Amicable Numbers", sorted by their minimal elements.
4

%I #21 Feb 19 2019 04:43:56

%S 35,155,142,224,272,601,1033,956,1847,2512,3004,2407,2224,3055,3357,

%T 4288,5637,4511,7536,5824,6460,7756,8637,7619,8721,7965,14044,14974,

%U 16992,13503,14656,14508,14108,18261,22576,17542,16251,20638,18108,29960,27328,24736

%N Maximal elements of pairs of "Super Unitary Amicable Numbers", sorted by their minimal elements.

%H Amiram Eldar, <a href="/A045614/b045614.txt">Table of n, a(n) for n = 1..40410</a> (terms below 10^10, terms 1..1000 from Donovan Johnson)

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SuperUnitaryAmicablePair.html">Super Unitary Amicable Pair</a>

%F usigma(usigma(a)) = usigma(usigma(b)) = a+b where a<b and usigma(n) = A034448(n) is the sum of the unitary divisors of n. This sequence gives the values of b; A045613 gives the values of a.

%t usigma[n_] := If[n == 1, 1, Times @@ (1 + Power @@@ FactorInteger[n])]; u[n_] := usigma[usigma[n]] - n; s = {}; Do[m = u[n]; If[m > n && u[m] == n, AppendTo[s, m]], {n, 1, 10000}]; s (* _Amiram Eldar_, Feb 18 2019 *)

%Y Cf. A045613, A034448.

%K nonn

%O 1,1

%A _Yasutoshi Kohmoto_

%E Edited by _Dean Hickerson_, Nov 06 2006

%E Offset corrected by _Donovan Johnson_, Jul 26 2012

%E More terms from _Amiram Eldar_, Feb 18 2019