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A154314
Numbers with not more than two distinct digits in ternary representation.
8
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 16, 17, 18, 20, 22, 23, 24, 25, 26, 27, 28, 30, 31, 36, 37, 39, 40, 41, 43, 44, 49, 50, 52, 53, 54, 56, 60, 62, 67, 68, 70, 71, 72, 74, 76, 77, 78, 79, 80, 81, 82, 84, 85, 90, 91, 93, 94, 108, 109, 111, 112, 117, 118, 120, 121, 122
OFFSET
1,3
COMMENTS
A043530(a(n)) <= 2; complement of A031944; union of A032924, A005823 and A005836.
A212193(a(n)) <> 3. - Reinhard Zumkeller, May 04 2012
LINKS
FORMULA
a(n) >> n^1.58..., where the exponent is log(3)/log(2). - Charles R Greathouse IV, Mar 17 2014
MATHEMATICA
Select[Range[0, 200], Length[Union[IntegerDigits[#, 3]]]<3&] (* Harvey P. Dale, Nov 23 2012 *)
PROG
(Haskell)
import Data.List (findIndices)
a154314 n = a154314_list !! (n-1)
a154314_list = findIndices (/= 3) a212193_list
-- Reinhard Zumkeller, May 04 2012
(PARI) is(n)=#Set(digits(n, 3))<3 \\ Charles R Greathouse IV, Mar 17 2014
CROSSREFS
Cf. A007089.
Sequence in context: A342382 A094270 A125705 * A239348 A191881 A306424
KEYWORD
base,nonn
AUTHOR
Reinhard Zumkeller, Jan 07 2009
STATUS
approved