OFFSET
0,3
LINKS
Harvey P. Dale, Table of n, a(n) for n = 0..1000
MAPLE
MATHEMATICA
nxt[{n_, a_}]:=Module[{d=DivisorSigma[0, n+1]}, {n+1, If[Divisible[a, d], a/d, a*d]}]; Transpose[NestList[nxt, {0, 1}, 70]][[2]] (* Harvey P. Dale, Jul 25 2015 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Jul 08 2008
EXTENSIONS
Extended beyond a(20) by R. J. Mathar, Aug 08 2008
STATUS
approved