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A122425
a(n) = lexicographically greatest divisor of n in decimal representation.
5
1, 2, 3, 4, 5, 6, 7, 8, 9, 5, 11, 6, 13, 7, 5, 8, 17, 9, 19, 5, 7, 22, 23, 8, 5, 26, 9, 7, 29, 6, 31, 8, 33, 34, 7, 9, 37, 38, 39, 8, 41, 7, 43, 44, 9, 46, 47, 8, 7, 50, 51, 52, 53, 9, 55, 8, 57, 58, 59, 60, 61, 62, 9, 8, 65, 66, 67, 68, 69, 70, 71, 9, 73, 74, 75, 76, 77, 78, 79, 80, 9, 82, 83
OFFSET
1,2
COMMENTS
a(p) = p for primes p;
a(A122427(n)) = A122427(n), a(A122426(n)) < A122426(n);
a(A122428(n)) = A006530(A122428(n)).
a(n) = A254679(n,A000005(n)). - Reinhard Zumkeller, Feb 05 2015
LINKS
EXAMPLE
Divisors(24) = [1,2,3,4,6,8,12,24] --> [1,12,2,24,3,4,6,8],
therefore a(24) = 8;
divisors(42) = [1,2,3,6,7,14,21,42] --> [1,14,2,21,3,42,6,7],
therefore a(42) = 7.
PROG
(Haskell)
import import Data.List (maximumBy); Data.Ord (comparing)
a122425 = maximumBy (comparing show) . a027750_row
-- Reinhard Zumkeller, Feb 05 2015, Sep 15 2011
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Sep 04 2006
STATUS
approved