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A072204
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a(n)-th factorial is the smallest factorial containing exactly n 7's, or 0 if no such number exists.
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8
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6, 14, 18, 31, 49, 22, 54, 48, 56, 71, 82, 72, 86, 81, 92, 97, 87, 122, 91, 119, 131, 112, 121, 140, 104, 152, 144, 173, 127, 157, 172, 201, 227, 179, 200, 187, 183, 210, 236, 221, 193, 217, 279, 212, 213, 235, 238, 289, 265, 228, 256, 261, 250, 242, 285, 307
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| a(2)=14 since 14-th factorial i.e. 14!=87178291200 contains exactly two 7's.
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MATHEMATICA
| Do[k = 1; While[ Count[IntegerDigits[k! ], 7] != n, k++ ]; Print[k], {n, 1, 60}]
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CROSSREFS
| Cf. A072238, A072220, A072208, A072200, A072199, A072178, A072177, A072163 & A072124.
Sequence in context: A156858 A032500 A053474 * A037177 A048747 A175678
Adjacent sequences: A072201 A072202 A072203 * A072205 A072206 A072207
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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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