OFFSET
1,1
COMMENTS
Suggested by A279070.
Primes are excluded by decree.
In the prime power factorization of p we write p rather than p^1.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..5100
EXAMPLE
10 = 2*5 is a term (both have 2 digits).
27 = 3^3 is a term (both have 2 digits).
MATHEMATICA
ndf[n_]:=Total[IntegerLength/@Select[Flatten[FactorInteger[n]], #!=1&]];
Select[Range[250], !PrimeQ[#]&&IntegerLength[#]==ndf[#]&] (* Ivan N. Ianakiev, Dec 28 2016 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Dec 27 2016
EXTENSIONS
a(14)-a(60) from Ivan N. Ianakiev, Dec 28 2016
STATUS
approved