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A060417
Number of different decimal digits in n-th prime.
2
1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 2, 3, 2, 3, 3, 3, 2, 3, 3, 3, 3, 3, 2, 2, 3, 3, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 2, 3, 3, 3, 3, 2, 2, 3, 2, 2, 3, 3, 2, 3, 3, 2, 3, 2, 3, 3, 3, 3, 3, 3, 3, 2, 3, 2, 2, 3, 3, 3, 3, 3, 3, 3, 2, 3, 3, 3, 3, 3, 3, 2, 3, 3, 3
OFFSET
1,6
LINKS
FORMULA
Table[Length[Union[IntegerDigits[Prime[w]]]], {w, 1, 1000}]
EXAMPLE
The maximum is 10. Thus 1234567891 is a prime with 9 and 123456789011 with 10 different decimal digits.
PROG
(Haskell)
import Data.List (nub, sort)
a060417 = length . nub . show . a000040
-- Reinhard Zumkeller, Apr 08 2012
CROSSREFS
Sequence in context: A077429 A204553 A214455 * A097944 A037203 A032556
KEYWORD
base,easy,nonn
AUTHOR
Labos Elemer, Apr 05 2001
STATUS
approved