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A108603 Numbers n such that n! can be written as the product of smaller distinct factorials in more than one way. 0
10, 720, 1440, 17280, 34560 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No other terms < 65000. This is a subsequence of A075082. All known members of the sequence exploit the fact that 6! = 5! * 3! (they must have 6! without either 5! or 3! in one solution). Factorizations: 10 = 2*5; 720 = 2^4 * 3^2 * 5; 1440 = 2^5 * 3^2 * 5; 17280 = 2^7 * 3^3 * 5; 34560 = 2^8 * 3^3 * 5;

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

34560! = 34559! * 6! * 4! * 2! = 34559! * 5! * 4! * 3! * 2!

CROSSREFS

Cf. A075082, A000142.

Sequence in context: A174061 A058174 A006435 * A053468 A008272 A015509

Adjacent sequences:  A108600 A108601 A108602 * A108604 A108605 A108606

KEYWORD

nonn,more

AUTHOR

Jud McCranie, Jun 13 2005

STATUS

approved

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Last modified May 21 18:43 EDT 2019. Contains 323444 sequences. (Running on oeis4.)