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A008521 Numbers that do not contain the letter `o'. 5
3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16, 17, 18, 19, 20, 23, 25, 26, 27, 28, 29, 30, 33, 35, 36, 37, 38, 39, 50, 53, 55, 56, 57, 58, 59, 60, 63, 65, 66, 67, 68, 69, 70, 73, 75, 76, 77, 78, 79, 80, 83, 85, 86, 87, 88, 89, 90, 93, 95, 96, 97, 98, 99, 300, 303, 305, 306, 307 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There are exactly 454 oban numbers, (Eric W. Weisstein, Nov 09, 2003).

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..454

Roel and Bas van Dijk, Numerals package, Hackage (Haskell packages)

Eric Weisstein's World of Mathematics, Oban Number

Index entries for sequences related to number of letters in n

PROG

(Haskell)

import Data.Maybe (fromJust)

import Data.Text (Text); import qualified Data.Text as T (all)

import Text.Numeral.Grammar.Reified (defaultInflection)

import qualified Text.Numeral.Language.EN as EN  -- see link

a008521 n = a008521_list !! (n-1)

a008521_list = filter (T.all (/= 'o') . numeral) [0..] where

   numeral :: Integer -> Text

   numeral = fromJust . EN.gb_cardinal defaultInflection

-- Reinhard Zumkeller, Jan 23 2015

CROSSREFS

Cf. A006933 (ban e), A089589 (ban i), A008523 (ban t), A089590 (ban u).

Sequence in context: A005527 A009005 A138884 * A039231 A194387 A039175

Adjacent sequences:  A008518 A008519 A008520 * A008522 A008523 A008524

KEYWORD

nonn,word,fini,full

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified December 7 23:55 EST 2016. Contains 278902 sequences.