A290142 Records of the maxima of the aliquot sequences of the numbers in A290141.

16, 21, 22, 55, 259, 759, 32571, 179931895322

Offset: 1

Author

Amiram Eldar, Jul 21 2017

Keywords

• nonn
• more

Comments

a(8) was calculated by D. H. Lehmer.

Examples

			The aliquot sequence of 30 is: 30, 42, 54, 66, 78, 90, 144, 259, 45, 33, 15, 9, 4, 3, 1. The maximum is 259 which is larger than 30, and larger than the maxima of all the aliquot sequences of the numbers below 30.
		

Crossrefs

Cf. A008888, A098008, A098009, A098010, A290141.

Programs

Mathematica

g[n_] := If[n > 0, DivisorSigma[1, n] - n, 0]; f[n_] := NestWhileList[g, n, UnsameQ, All]; rec = {}; a = -1; seq = {}; Do[b = Max[Drop[f[n], 1]];
If[b > a, a = b; AppendTo[rec, b]], {n, 2, 275}] ; rec (* after Robert G. Wilson v at A098009 *)