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A072177
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a(n)-th factorial is the smallest factorial containing exactly n 3's, or 0 if no such number exists.
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8
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8, 15, 25, 36, 24, 49, 32, 54, 43, 69, 76, 89, 84, 113, 82, 105, 112, 92, 114, 106, 118, 107, 109, 151, 166, 143, 160, 149, 190, 152, 158, 172, 176, 0, 192, 181, 183, 177, 180, 202, 200, 193, 226, 238, 242, 223, 251, 227, 290, 261, 267, 292, 265, 300, 295, 285
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| It is conjectured that a(34)=0 since no factorial < 10000 contained just 34 threes.
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EXAMPLE
| a(2)=15 since 15-th factorial i.e. 15!=1307674368000 contains exactly two 3's.
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MATHEMATICA
| Do[k = 1; While[ Count[IntegerDigits[k! ], 3] != n, k++ ]; Print[k], {n, 1, 60}]
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CROSSREFS
| Cf. A072269, A072220, A072208, A072204, A072200, A072199, A072178, A072163 & A072124.
Sequence in context: A034114 A069826 A129076 * A169875 A031125 A132298
Adjacent sequences: A072174 A072175 A072176 * A072178 A072179 A072180
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KEYWORD
| base,nonn
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AUTHOR
| Shyam Sunder Gupta (guptass(AT)rediffmail.com), Jul 30 2002
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EXTENSIONS
| Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Jul 31 2002
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