A089589 - OEIS

%I #20 Aug 05 2022 07:45:26

%S 0,1,2,3,4,7,10,11,12,14,17,20,21,22,23,24,27,40,41,42,43,44,47,70,71,

%T 72,73,74,77,100,101,102,103,104,107,110,111,112,114,117,120,121,122,

%U 123,124,127,140,141,142,143,144,147,170,171,172,173,174,177,200,201

%N Iban numbers (the letter i is banned from the English name of the number).

%C Blind numbers. - _Cino Hilliard_, May 03 2004

%C There are 30276 terms, ending in 777777. - _Michael S. Branicky_, Aug 04 2022

%H Michael S. Branicky, <a href="/A089589/b089589.txt">Table of n, a(n) for n = 1..30276</a> (full sequence; terms 1..10000 from Reinhard Zumkeller)

%H Roel and Bas van Dijk, <a href="http://hackage.haskell.org/package/numerals">Numerals package</a>, Hackage (Haskell packages).

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/IbanNumber.html">Iban Number</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Names_of_large_numbers">Names of Large Numbers</a>

%H <a href="/index/Lc#letters">Index entries for sequences related to number of letters in n</a>

%o (Haskell)

%o import Data.Maybe (fromJust)

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

%o import Text.Numeral.Grammar.Reified (defaultInflection)

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

%o a089589 n = a089589_list !! (n-1)

%o a089589_list = filter (T.all (/= 'i') . numeral) [0..] where

%o    numeral :: Integer -> Text

%o    numeral = fromJust . EN.gb_cardinal defaultInflection

%o -- _Reinhard Zumkeller_, Jan 23 2015

%o (Python)

%o from itertools import islice

%o from num2words import num2words

%o def agen(): yield from (k for k in range(10**6) if "i" not in num2words(k))

%o print(list(islice(agen(), 60))) # _Michael S. Branicky_, Aug 04 2022

%Y Cf. A006933 (ban e), A008521 (ban o), A008523 (ban t), A089590 (ban u).

%K nonn,easy,word,fini,full

%O 1,3

%A _Eric W. Weisstein_, Nov 09 2003