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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
OFFSET
1,2
COMMENTS
Next term after 42862 (if it exists) is greater than 750,000.
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: A350233 A278855 A137186 * A223888 A211572 A087239
KEYWORD
base,hard,more,nonn
AUTHOR
Ryan Propper, Aug 06 2005
STATUS
approved