

A025283


Composites that use the same digits as their prime factorization.


15



25, 121, 1255, 2349, 5120, 12337, 12955, 17482, 25105, 41323, 43375, 93217, 100255, 101299, 105295, 107329, 117067, 124483, 127417, 129595, 132565, 145273, 146137, 149782, 163797, 174082, 174298, 174793, 174982, 191239, 250105, 256315, 263155
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OFFSET

1,1


COMMENTS

Here exponents equal to 1 are not taken into account, so 1255 = 5^1*251^1 = 5*251 is a term. Prime numbers are excluded because they all trivially use the same digits as their prime factorization. If, on the contrary, exponents equal to 1 are counted, the resulting sequence is A075047.  Giovanni Resta, Jul 14 2015
An interesting example of the factorization digits appearing in the same order as in its composite generator: 13532385396179 = 13 * 53^2 * 3853 * 96179.  Hans Havermann, Jun 28 2017


LINKS



MATHEMATICA

Select[Range[10^5], !PrimeQ@ # && Sort@ IntegerDigits@ # == Sort@ Flatten@ IntegerDigits@ Select[ Flatten@ FactorInteger@ #, #>1 &] &] (* Giovanni Resta, Jul 14 2015 *)


CROSSREFS

Cf. A075047, A260046, A260047, A260048, A260049, A260050, A260051, A260052, A260053, A260054, A260055.


KEYWORD

base,nonn


AUTHOR



STATUS

approved



