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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 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.)