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A108858 Numbers n such that n divides the sum of the digits of n!!, the double factorial of n. 0
1, 2, 3, 4, 6, 9, 51, 57, 252, 585, 1131, 2106, 2172, 2250, 2292, 26159, 26769, 27253, 28071, 46802, 47148, 48018 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Next term after 48018, if it exists, is greater than 100,000.

LINKS

Table of n, a(n) for n=1..22.

Eric Weisstein. "Double Factorial."

EXAMPLE

585 is a term because the sum of the digits of 585!! = 2925 is divisible by 585.

MATHEMATICA

Do[If[Mod[Plus @@ IntegerDigits[n!! ], n] == 0, Print[n]], {n, 1, 100000}]

CROSSREFS

Sequence in context: A275173 A295394 A081419 * A294688 A094859 A267102

Adjacent sequences:  A108855 A108856 A108857 * A108859 A108860 A108861

KEYWORD

base,hard,more,nonn

AUTHOR

Ryan Propper, Jul 11 2005

STATUS

approved

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Last modified April 20 20:26 EDT 2021. Contains 343137 sequences. (Running on oeis4.)