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A309953
Product of digits of (n written in base 3).
5
0, 1, 2, 0, 1, 2, 0, 2, 4, 0, 0, 0, 0, 1, 2, 0, 2, 4, 0, 0, 0, 0, 2, 4, 0, 4, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 0, 2, 4, 0, 0, 0, 0, 2, 4, 0, 4, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 0, 4, 8, 0, 0, 0, 0, 4, 8, 0, 8, 16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
0,3
LINKS
FORMULA
G.f. A(x) satisfies: A(x) = x * (1 + 2*x) * (1 + A(x^3)).
MAPLE
a:= proc(n) a(n):= `if`(n<3, n, irem(n, 3, 'q')*a(q)) end:
seq(a(n), n=0..100); # Alois P. Heinz, Mar 18 2024
MATHEMATICA
Table[Times @@ IntegerDigits[n, 3], {n, 0, 100}]
PROG
(PARI) a(n) = {if(n, vecprod(digits(n, 3)), 0)} \\ Andrew Howroyd, Aug 24 2019
(Magma) [0] cat [&*Intseq(n, 3):n in [1..100]]; // Marius A. Burtea, Aug 25 2019
CROSSREFS
KEYWORD
nonn,base,look
AUTHOR
Ilya Gutkovskiy, Aug 24 2019
STATUS
approved