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A037373 Positive numbers k such that every base-2 digit of k is a base-4 digit of k. 8
1, 4, 7, 16, 17, 18, 19, 20, 24, 28, 31, 33, 36, 49, 52, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 88, 92, 96, 97, 98, 99, 100, 104, 108, 112, 113, 114, 115, 116, 120, 124, 127, 129, 132, 133, 134 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

PROG

(Haskell)

import Data.List ((\\), nub)

a037373 n = a037373_list !! (n-1)

a037373_list = filter f [1..] where

   f x = null $ nub (ds 2 x) \\ nub (ds 4 x)

   ds b x = if x > 0 then d : ds b x' else []  where (x', d) = divMod x b

-- Reinhard Zumkeller, May 30 2013

CROSSREFS

Cf. A037372, A037374, A037375, A037376, A037377, A037378, A037379.

Sequence in context: A166669 A286701 A077582 * A310928 A018887 A059014

Adjacent sequences:  A037370 A037371 A037372 * A037374 A037375 A037376

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified June 24 04:02 EDT 2021. Contains 345416 sequences. (Running on oeis4.)