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!)
A072200 a(n)-th factorial is the smallest factorial containing exactly n 6's, or 0 if no such number exists. 8
3, 15, 23, 26, 32, 41, 35, 45, 50, 72, 63, 83, 84, 98, 89, 94, 91, 121, 99, 142, 117, 160, 129, 0, 127, 131, 132, 154, 153, 163, 170, 179, 190, 178, 166, 189, 217, 209, 206, 174, 208, 199, 207, 211, 214, 245, 263, 175, 240, 255, 295, 234, 213, 296, 286, 266, 278 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

It is conjectured that a(24)=0 since no factorial < 10000 contained just 24 sixes.

LINKS

Table of n, a(n) for n=1..57.

EXAMPLE

a(2)=15 since the 15th factorial, i.e., 15!=1307674368000, contains exactly two 6's.

MATHEMATICA

Do[k = 1; While[ Count[IntegerDigits[k! ], 6] != n, k++ ]; Print[k], {n, 1, 60}]

CROSSREFS

Cf. A072240, A072220, A072208, A072204, A072199, A072178, A072177, A072163 & A072124.

Sequence in context: A083793 A324127 A083934 * A106403 A225365 A225060

Adjacent sequences:  A072197 A072198 A072199 * A072201 A072202 A072203

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, Jul 30 2002

EXTENSIONS

Edited and extended by Robert G. Wilson v, Jul 31 2002

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 28 14:19 EDT 2021. Contains 346335 sequences. (Running on oeis4.)