A072238 Smallest factorial containing exactly n 7's.

720, 87178291200, 6402373705728000, 8222838654177922817725562880000000, 608281864034267560872252163321295376887552831379210240000000000, 1124000727777607680000, 230843697339241380472092742683027581083278564571807941132288000000000000

Offset

1,1

Links

Table of n, a(n) for n=1..7.

Example

a(2)=87178291200 so 87178291200 is the smallest factorial containing exactly two 7's.

Mathematica

With[{f=Range[200]!}, Table[SelectFirst[f, DigitCount[#, 10, 7]==n&], {n, 6}]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 07 2019 *)

Crossrefs

Sequence in context: A172621 A367570 A294323 * A271946 A172727 A283048

Adjacent sequences: A072235 A072236 A072237 * A072239 A072240 A072241

Keyword

base,nonn

Author

Shyam Sunder Gupta, Jul 30 2002

Extensions

a(7) from Harvey P. Dale, Aug 07 2019

Status

approved