A197181 Numbers that are a divisor of the product of the factorials of their digits in decimal representation.

1, 2, 3, 4, 5, 6, 7, 8, 9, 15, 16, 18, 24, 28, 36, 45, 48, 60, 64, 70, 72, 75, 80, 84, 90, 96, 98, 128, 144, 168, 175, 180, 189, 192, 256, 280, 288, 360, 378, 384, 448, 480, 486, 567, 576, 588, 640, 648, 672, 675, 720, 729, 756, 768, 784, 840, 864, 875, 882

Offset

1,2

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

Example

a(10)=15: A066459(15) = 1!*5! = 120 = 15 * 8;
a(11)=16: A066459(16) = 1!*6! = 720 = 16 * 45;
17 is not a term because 5040 mod 17 = 8, A066459(16) = 5040;
a(12)=18: A066459(15) = 1!*8! = 40320 = 18 * 2240.

Mathematica

Select[Range[900], IntegerQ[Times@@(IntegerDigits[#]!)/#]&] (* Harvey P. Dale, Jul 07 2019 *)

Prog

(Haskell)
import Data.List (elemIndices)
a197181 n = a197181_list !! (n-1)
a197181_list = map (+ 1) $ elemIndices 0 $
   zipWith mod (map a066459 [1..]) [1..]

Crossrefs

Cf. A066459, A000142, A188264.

Sequence in context: A069118 A328933 A032978 * A260352 A049101 A287336

Adjacent sequences: A197178 A197179 A197180 * A197182 A197183 A197184

Keyword

nonn,base

Author

Reinhard Zumkeller, Oct 11 2011

Status

approved