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A072208 a(n)-th factorial is the smallest factorial containing exactly n 8's, or 0 if no such number exists. 8
11, 9, 36, 16, 30, 27, 39, 33, 44, 58, 56, 64, 80, 70, 72, 94, 97, 71, 108, 143, 120, 134, 118, 162, 125, 133, 151, 137, 138, 159, 169, 197, 184, 171, 178, 176, 206, 177, 191, 208, 207, 240, 252, 232, 239, 270, 229, 308, 243, 223, 278, 257, 250, 0, 303, 242, 311 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

It is conjectured that a(54)=0 since no factorial < 10000 contained just 54 eights.

LINKS

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

EXAMPLE

a(2)=9 since 9th factorial i.e. 9!=362880 contains exactly two 8's.

MATHEMATICA

Do[k = 1; While[ Count[IntegerDigits[k! ], 8] != n, k++ ]; Print[k], {n, 1, 60}]

Transpose[Flatten[Table[Select[Table[{n, DigitCount[n!, 10, 8]}, {n, 500}], Last[#] == i&, 1], {i, 50}], 1]][[1]] (* Harvey P. Dale, Sep 13 2013 *)

CROSSREFS

Cf. A072237, A072220, A072204, A072200, A072199, A072178, A072177, A072163, A072124.

Sequence in context: A316450 A196006 A196003 * A210284 A219746 A335854

Adjacent sequences:  A072205 A072206 A072207 * A072209 A072210 A072211

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, Jul 30 2002

EXTENSIONS

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

STATUS

approved

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Last modified August 12 05:33 EDT 2020. Contains 336438 sequences. (Running on oeis4.)