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A037378
Positive numbers k such that every base-2 digit of k is a base-9 digit of k.
8
1, 9, 15, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 99, 108, 117, 126, 127, 135, 144, 153, 163, 171, 244, 252, 255, 325, 333, 406, 414, 487, 495, 568, 576, 649, 657, 729, 730, 731, 732, 733, 734, 735, 736, 737, 738, 739, 740, 741
OFFSET
1,2
LINKS
MATHEMATICA
Select[Range[800], SubsetQ[Union[IntegerDigits[#, 9]], Union[IntegerDigits[#, 2]]]&] (* Harvey P. Dale, Jan 12 2024 *)
PROG
(Haskell)
import Data.List ((\\), nub)
a037378 n = a037378_list !! (n-1)
a037378_list = filter f [1..] where
f x = null $ nub (ds 2 x) \\ nub (ds 9 x)
ds b x = if x > 0 then d : ds b x' else [] where (x', d) = divMod x b
-- Reinhard Zumkeller, May 30 2013
KEYWORD
nonn,base
STATUS
approved