OFFSET
1,1
COMMENTS
We also have a(18)=18174907880, a(19)=81418065258, a(20)=257678968520, and a(23)=529539876740. The missing terms are all greater than 10^12.
EXAMPLE
a(1)=203457869, whose divisors are 1 and 203457869 itself. a(2)=206893558, whose divisors, i.e., 1, 2, 103446779, and 206893558, contain each digit 2 times.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, May 15 2016
STATUS
approved