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%I #23 Sep 08 2022 08:46:20
%S 1,1,2,6,8,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%T 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%U 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%N Product of digits of n!.
%C Also multiplicative digital root of n!.
%C a(n) = 0 for n >= 5.
%C Decimal expansion of 2817/2500. - _Eric Chen_, Jun 06 2018
%F a(n) = A031347(A000142(n)).
%F a(n) = A007954(A000142(n)). - _Eric Chen_, Jun 06 2018
%t Array[Times @@ IntegerDigits[#!] &, 105] (* _Michael De Vlieger_, Jun 06 2018 *)
%o (Magma) [&*Intseq(Factorial(n)): n in [0..100]]
%o (PARI) a(n) = my(d=digits(n!)); prod(k=1, #d, d[k]); \\ _Michel Marcus_, Jun 05 2018
%Y Cf. A000142, A007954, A031347, A067067, A086358, A004152.
%K nonn,base
%O 0,3
%A _Jaroslav Krizek_, Jun 05 2018
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