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A037377
Positive numbers k such that every base-2 digit of k is a base-8 digit of k.
8
1, 8, 15, 64, 65, 66, 67, 68, 69, 70, 71, 72, 80, 88, 96, 104, 112, 120, 127, 129, 136, 193, 200, 257, 264, 321, 328, 385, 392, 449, 456, 512, 513, 514, 515, 516, 517, 518, 519, 520, 521, 522, 523, 524, 525, 526, 527, 528, 529, 530
OFFSET
1,2
LINKS
PROG
(Haskell)
import Data.List ((\\), nub)
a037377 n = a037377_list !! (n-1)
a037377_list = filter f [1..] where
f x = null $ nub (ds 2 x) \\ nub (ds 8 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