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%I #25 Nov 22 2023 15:07:30
%S 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,
%T 16,19,17,12,21,21,16,21,20,24,23,24,25,26,25,24,22,31,31,29,31,37,30,
%U 32,36,32,35,34,37,36,39,39,41,38,39,51,47,48,35,42,48
%N Sum of digits of n! divided by 9.
%C (sum of digits of n!) / 9 is an integer for n > 5.
%H Seiichi Manyama, <a href="/A202708/b202708.txt">Table of n, a(n) for n = 6..10000</a>
%F a(n) = A004152(n)/9.
%t Table[Sum[DigitCount[n!][[i]]*i/9, {i, 1, 9}], {n, 6, 100}]
%t Total[IntegerDigits[#]]/9&/@(Range[6,80]!) (* _Harvey P. Dale_, Nov 22 2023 *)
%o (PARI) a(n) = sumdigits(n!)/9; \\ _Michel Marcus_, Aug 12 2022
%Y Cf. A004152, A086358.
%K nonn,base,easy
%O 6,4
%A _Michel Lagneau_, Dec 23 2011
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