login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A338803 Product of the nonzero digits of (n written in base 5). 1
1, 1, 2, 3, 4, 1, 1, 2, 3, 4, 2, 2, 4, 6, 8, 3, 3, 6, 9, 12, 4, 4, 8, 12, 16, 1, 1, 2, 3, 4, 1, 1, 2, 3, 4, 2, 2, 4, 6, 8, 3, 3, 6, 9, 12, 4, 4, 8, 12, 16, 2, 2, 4, 6, 8, 2, 2, 4, 6, 8, 4, 4, 8, 12, 16, 6, 6, 12, 18, 24, 8, 8, 16, 24, 32, 3, 3, 6, 9, 12, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..80.

FORMULA

G.f. A(x) satisfies: A(x) = (1 + x + 2*x^2 + 3*x^3 + 4*x^4) * A(x^5).

MATHEMATICA

Table[Times @@ DeleteCases[IntegerDigits[n, 5], 0], {n, 0, 80}]

nmax = 80; A[_] = 1; Do[A[x_] = (1 + x + 2 x^2 + 3 x^3 + 4 x^4) A[x^5] + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x]

PROG

(PARI) a(n) = vecprod(select(x->x, digits(n, 5))); \\ Michel Marcus, Nov 12 2020

CROSSREFS

Cf. A007091, A051801, A117592, A309956.

Sequence in context: A139458 A277543 A190594 * A104412 A195451 A298160

Adjacent sequences:  A338800 A338801 A338802 * A338804 A338805 A338806

KEYWORD

nonn,base

AUTHOR

Ilya Gutkovskiy, Nov 12 2020

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 30 15:29 EDT 2021. Contains 346359 sequences. (Running on oeis4.)