OFFSET
1,2
EXAMPLE
138 has a transient of length 177 (see Guy's book).
MATHEMATICA
g[n_] := If[n > 0, DivisorSigma[1, n] - n, 0]; f[n_] := NestWhileList[g, n, UnsameQ, All]; a = -1; Do[b = Length[ f[n]] - 2; If[b > a, a = b; Print[b]], {n, 275}] (* Robert G. Wilson v, Sep 10 2004 *)
CROSSREFS
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Sep 10 2004
EXTENSIONS
18 and 178 from Robert G. Wilson v, Sep 10 2004
STATUS
approved