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A066459 Product of factorials of the digits of n. 7
1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880, 1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880, 2, 2, 4, 12, 48, 240, 1440, 10080, 80640, 725760, 6, 6, 12, 36, 144, 720, 4320, 30240, 241920, 2177280, 24, 24, 48, 144, 576, 2880, 17280, 120960, 967680 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Harry J. Smith and Indranil Ghosh, Table of n, a(n) for n = 0..10000 (first 1001 terms from Harry J. Smith)

Eric Weisstein's World of Mathematics, Factorial

Index entries for sequences related to factorial numbers

FORMULA

If n=10*q+r,(0<=r<10) then a(n)=(q+1+r)!*(sum((-1)^(q-k)*binomial(r,k)/(q+1+r-k),k=0..r)); Milan Janjic, Dec 14 2008]

EXAMPLE

a(24) = (2!) * (4!) = 2 * 24 = 48.

MAPLE

A066459 := proc(n)

    local a, d;

    a := 1 ;

    for d in convert(n, base, 10) do

        a := a*d! ;

    end do:

    a ;

end proc: # R. J. Mathar, Aug 07 2014

PROG

(PARI) { for (n=0, 1000, m=n; a=1; while (m>0, d=m%10; m=(m-d)/10; a*=d!); write("b066459.txt", n, " ", a) ) } \\ Harry J. Smith, Feb 15 2010

(Haskell)

import Data.List (unfoldr)

a066459 = product . map a000142 .

   unfoldr (\x -> if x == 0 then Nothing else Just $ swap $ divMod x 10)

-- Reinhard Zumkeller, Oct 11 2011

(Python)

import math

def A066459(n):

    s=1

    for i in str(n):

        s*=math.factorial(int(i))

    return s # Indranil Ghosh, Jan 11 2017

CROSSREFS

Cf. A000142, A034879 (iterated).

Sequence in context: A248841 A072132 A230231 * A269221 A071937 A061602

Adjacent sequences:  A066456 A066457 A066458 * A066460 A066461 A066462

KEYWORD

base,easy,nonn

AUTHOR

Jason Earls, Jan 02 2002

STATUS

approved

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Last modified April 18 08:37 EDT 2019. Contains 322209 sequences. (Running on oeis4.)