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%I #18 Sep 08 2022 08:46:22
%S 0,1,2,3,4,5,6,0,1,2,3,4,5,6,0,2,4,6,8,10,12,0,3,6,9,12,15,18,0,4,8,
%T 12,16,20,24,0,5,10,15,20,25,30,0,6,12,18,24,30,36,0,0,0,0,0,0,0,0,1,
%U 2,3,4,5,6,0,2,4,6,8,10,12,0,3,6,9,12,15,18,0,4,8,12,16,20,24,0,5,10,15,20,25,30,0,6,12,18,24,30,36,0,0,0
%N Product of digits of (n written in base 7).
%H Seiichi Manyama, <a href="/A309958/b309958.txt">Table of n, a(n) for n = 0..10000</a>
%F G.f. A(x) satisfies: A(x) = x * (1 + 2*x + 3*x^2 + 4*x^3 + 5*x^4 + 6*x^5) * (1 + A(x^7)).
%t Table[Times @@ IntegerDigits[n, 7], {n, 0, 100}]
%o (Magma) [0] cat [&*Intseq(n,7):n in [1..100]]; // _Marius A. Burtea_, Aug 25 2019
%o (PARI) a(n) = my(v=vecprod(digits(n, 7))); n>0 && return(v) \\ _Felix Fröhlich_, Sep 09 2019
%Y Product of digits of (n written in base k): A309953 (k = 3), A309954 (k = 4), A309956 (k = 5), A309957 (k = 6), this sequence (k = 7), A309959 (k = 8), A309788 (k = 9), A007954 (k = 10).
%Y Cf. A007093, A053828.
%K nonn,base
%O 0,3
%A _Ilya Gutkovskiy_, Aug 24 2019
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