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A093642 Numbers not containing all divisors in their binary representation. 5
9, 15, 18, 21, 25, 27, 30, 33, 35, 36, 39, 42, 45, 49, 50, 51, 54, 57, 60, 63, 65, 66, 69, 70, 72, 75, 77, 78, 81, 84, 85, 87, 90, 91, 93, 95, 98, 99, 100, 102, 105, 108, 110, 111, 114, 115, 117, 119, 120, 121, 123, 125, 126, 129, 130, 132, 133, 135, 138, 140, 141 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

55 is not a member, as the binary representations of 5 ("101") and 11 ("1011") both appear in the binary representation of 55 ("110111").

PROG

(Haskell)

import Data.List (unfoldr, isInfixOf)

a093642 n = a093642_list !! (n-1)

a093642_list = filter

  (\x -> not $ all (`isInfixOf` b x) $ map b $ a027750_row x) [1..] where

  b = unfoldr (\x -> if x == 0 then Nothing else Just $ swap $ divMod x 2)

-- Reinhard Zumkeller, Oct 27 2012

CROSSREFS

A093640(a(n)) < A000005(a(n)).

Subsequence of A105441. - Reinhard Zumkeller, Apr 09 2005

Cf. A078822, A007088. Complement of A123345.

Cf. A027750.

Sequence in context: A110473 A105441 A325164 * A177733 A207675 A118236

Adjacent sequences:  A093639 A093640 A093641 * A093643 A093644 A093645

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, Apr 07 2004

STATUS

approved

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Last modified April 14 12:11 EDT 2021. Contains 342949 sequences. (Running on oeis4.)