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 A338863 Product of the nonzero digits of (n written in base 6). 1
 1, 1, 2, 3, 4, 5, 1, 1, 2, 3, 4, 5, 2, 2, 4, 6, 8, 10, 3, 3, 6, 9, 12, 15, 4, 4, 8, 12, 16, 20, 5, 5, 10, 15, 20, 25, 1, 1, 2, 3, 4, 5, 1, 1, 2, 3, 4, 5, 2, 2, 4, 6, 8, 10, 3, 3, 6, 9, 12, 15, 4, 4, 8, 12, 16, 20, 5, 5, 10, 15, 20, 25, 2, 2, 4, 6, 8, 10, 2, 2, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS FORMULA G.f. A(x) satisfies: A(x) = (1 + x + 2*x^2 + 3*x^3 + 4*x^4 + 5*x^5) * A(x^6). MATHEMATICA Table[Times @@ DeleteCases[IntegerDigits[n, 6], 0], {n, 0, 80}] nmax = 80; A[_] = 1; Do[A[x_] = (1 + x + 2 x^2 + 3 x^3 + 4 x^4 + 5 x^5) A[x^6] + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x] PROG (PARI) a(n) = vecprod(select(x->x, digits(n, 6))); \\ Michel Marcus, Nov 13 2020 CROSSREFS Cf. A007092, A051801, A117592, A309957. Sequence in context: A339256 A277544 A190595 * A280502 A276757 A290397 Adjacent sequences:  A338860 A338861 A338862 * A338864 A338865 A338866 KEYWORD nonn,base AUTHOR Ilya Gutkovskiy, Nov 12 2020 STATUS approved

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Last modified July 25 03:53 EDT 2021. Contains 346283 sequences. (Running on oeis4.)