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A202708
Sum of digits of n! divided by 9.
2
1, 1, 1, 3, 3, 4, 3, 3, 5, 5, 7, 7, 6, 5, 6, 7, 8, 11, 9, 8, 9, 12, 10, 14, 13, 15, 12, 16, 16, 16, 19, 17, 12, 21, 21, 16, 21, 20, 24, 23, 24, 25, 26, 25, 24, 22, 31, 31, 29, 31, 37, 30, 32, 36, 32, 35, 34, 37, 36, 39, 39, 41, 38, 39, 51, 47, 48, 35, 42, 48
OFFSET
6,4
COMMENTS
(sum of digits of n!) / 9 is an integer for n > 5.
LINKS
FORMULA
a(n) = A004152(n)/9.
MATHEMATICA
Table[Sum[DigitCount[n!][[i]]*i/9, {i, 1, 9}], {n, 6, 100}]
Total[IntegerDigits[#]]/9&/@(Range[6, 80]!) (* Harvey P. Dale, Nov 22 2023 *)
PROG
(PARI) a(n) = sumdigits(n!)/9; \\ Michel Marcus, Aug 12 2022
CROSSREFS
Sequence in context: A121937 A003034 A091282 * A027684 A276864 A342928
KEYWORD
nonn,base,easy
AUTHOR
Michel Lagneau, Dec 23 2011
STATUS
approved