login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A247757
Numbers in decimal representation, such that in Italian and Portuguese their digits are in alphabetic order.
17
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 20, 21, 22, 23, 24, 26, 27, 28, 29, 30, 31, 33, 40, 41, 43, 44, 46, 47, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 63, 66, 67, 70, 71, 73, 77, 80, 81, 83, 84, 86, 87, 88, 90, 91, 93, 94, 96, 97, 98, 99, 100, 110
OFFSET
1,3
COMMENTS
List of decimal digits, alphabetically sorted by their names in Italian resp. Portuguese: 5 _ cinque _ cinco, 2 _ due _ dois/duas, 9 _ nove _ nove, 8 _ otto _ oito, 4 _ quattro _ quatro, 6 _ sei _ seis, 7 _ sette _ sete, 3 _ tre _ tres, 1 _ uno _ um, 0 _ zero _ zero;
a(129217) = A247807(1023) = 5298467310 is the greatest term not containing any repeating digits.
PROG
(Haskell)
import Data.IntSet (fromList, deleteFindMin, union)
a247757 n = a247757_list !! (n-1)
a247757_list = 0 : f (fromList [1..9]) where
f s = x : f (s' `union`
fromList (map (+ 10 * x) $ dropWhile (/= mod x 10) digs))
where (x, s') = deleteFindMin s
digs = [5, 2, 9, 8, 4, 6, 7, 3, 1, 0]
CROSSREFS
Cf. A247807 (subsequence).
Cf. A247750 (Czech), A247751 (Danish), A247752 (Dutch), A053432 (English), A247753 (Finnish), A247754 (French), A247755 (German), A247756 (Hungarian), A247758 (Latin), A247759 (Norwegian), A247760 (Polish), A247761 (Russian), A247762 (Slovak), A161390 (Spanish), A247759 (Swedish), A247764 (Turkish).
Sequence in context: A275413 A273376 A247758 * A247754 A084383 A032873
KEYWORD
nonn,base,word
AUTHOR
Reinhard Zumkeller, Oct 05 2014
STATUS
approved