A097037 Initial values for iteration of A063919(x) function such that iteration ends in a 2-cycle, i.e., "attracted" by unitary amicable numbers, A063991.

102, 114, 126, 388, 436, 484, 812, 866, 1020, 1036, 1040, 1116, 1140, 1196, 1260, 1380, 1500, 1524, 1532, 1552, 1618, 1644, 1716, 1724, 1726, 1744, 1916, 2020, 2066, 2068, 2324, 2368, 2386, 2486, 2592, 2684, 2880, 2924, 3032, 3098, 3120, 3124, 3136

Offset: 1

Author

Labos Elemer, Aug 30 2004

Keywords

• nonn

Examples

			n = 866: list = {866, 436, 114, 126, 114} ending in 2-cycle of [114, 126].
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A002827, A063919, A063991, A097024, A097030-A097036.

Programs

Mathematica

s[n_] := If[n > 1, Times @@ (1 + Power @@@ FactorInteger[n]) - n, 0]; useq[n_] := Most[NestWhileList[s, n, UnsameQ, All]]; amiQ[k_] := Module[{s1 = s[k]}, s1 != k && s[s1] == k]; aQ[n_] := amiQ[Last[useq[n]]]; Select[Range[5000], aQ] (* Amiram Eldar, Apr 06 2019 *)