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A068186 a(n) is the largest number whose product of decimal digits equals n^n. 0
22, 333, 22222222, 55555, 333333222222, 7777777, 222222222222222222222222, 333333333333333333, 55555555552222222222, 0, 3333333333332222222222222222222222222, 0, 7777777777777722222222222222 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

No digit=1 is permitted to avoid infinite number of solutions; a(n)=0 if A067734(n^n)=0.

LINKS

Table of n, a(n) for n=2..14.

FORMULA

a(n) is obtained as prime-factors of n^n concatenated in order of magnitude and with repetitions; a(n)=0 if n has p>7 prime factors.

EXAMPLE

n=10, 10^10=10000000000, a(5)=55555555552222222222

CROSSREFS

Cf. A000312, A001222, A002473, A067734, A068183-A068187, A068189-A068191.

Sequence in context: A000461 A216730 A048795 * A021284 A019623 A021794

Adjacent sequences:  A068183 A068184 A068185 * A068187 A068188 A068189

KEYWORD

base,nonn

AUTHOR

Labos Elemer, Feb 19 2002

STATUS

approved

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Last modified November 27 08:17 EST 2014. Contains 250165 sequences.