OFFSET
2,1
COMMENTS
Maximal solutions are obtained from the concatenation of distinct prime factors that have one decimal digit. The sequence is finite because, for n>10, n! has 2-digit prime factors.
FORMULA
a(n)=Max{x; f[x]=n!}, where x has no digit=1 and f[x_] := Apply[Times, IntegerDigits[x]].
CROSSREFS
KEYWORD
base,fini,nonn,full
AUTHOR
Labos Elemer, Feb 18 2002
STATUS
approved