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A109676 Numbers n such that the sum of the digits of (n! - 1) is divisible by n. 0
1, 25, 68, 269, 427, 1996, 5405, 42511, 42862 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Next term after 42862 (if it exists) is greater than 750,000.

LINKS

Table of n, a(n) for n=1..9.

EXAMPLE

The digits of 5405! - 1 sum to 86480 and 86480 is divisible by 5405, so 5405 is in the sequence.

MATHEMATICA

Do[k = n! - 1; s = Plus @@ IntegerDigits[k]; If[Mod[s, n] == 0, Print[n]], {n, 1, 10^5}]

CROSSREFS

Sequence in context: A211462 A278855 A137186 * A223888 A211572 A087239

Adjacent sequences:  A109673 A109674 A109675 * A109677 A109678 A109679

KEYWORD

base,hard,more,nonn

AUTHOR

Ryan Propper, Aug 06 2005

STATUS

approved

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Last modified June 4 17:50 EDT 2020. Contains 334828 sequences. (Running on oeis4.)