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A235708
Largest base in which n is pandigital.
1
1, 2, 1, 2, 2, 2, 1, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 3, 3, 3, 3, 2, 2, 3, 2, 2, 2, 3, 2, 2, 3, 3, 3, 3, 2, 2, 3, 2, 2, 2, 3, 2, 3, 3, 3, 2, 3, 2, 3, 3, 3, 3, 2, 2, 3, 2, 2, 2, 3, 2, 4, 2, 2, 4, 2, 2
OFFSET
1,2
COMMENTS
The first occurrence of k in this sequence is given by A049363(k).
LINKS
Eric Weisstein's World of Mathematics, Pandigital Number
PROG
(Haskell)
import Data.List (unfoldr, nub); import Data.Tuple (swap)
a235708 n = f n where
f 1 = 1
f b = if isPandigital b n then b else f (b - 1) where
isPandigital b = (== b) . length . nub . unfoldr
(\x -> if x == 0 then Nothing else Just $ swap $ divMod x b)
-- Reinhard Zumkeller, May 12 2014
CROSSREFS
Cf. A049363.
Sequence in context: A066086 A323406 A160520 * A353929 A297770 A330617
KEYWORD
nonn,base,nice
AUTHOR
Joonas Pohjonen, May 02 2014
STATUS
approved