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A096347
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Least number with n preimages (or immediate predecessors) under f(n) = n + (product of nonzero digits of n).
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13
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1, 2, 12, 102, 116, 1098, 2072, 1014, 101134, 11014, 1011098, 1003525, 41021255, 210110985, 403130555, 481104655, 4401225555, 4811125555, 86413249555, 39011218055
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| First occurrence of k in A096972.
a(20) > 10^11. [From Donovan Johnson (donovan.johnson(AT)yahoo.com), Nov 22 2009]
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REFERENCES
| P. A. Loomis, An Introduction to Digit Product Sequences (see link).
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LINKS
| P. A. Loomis, An Interesting Family of Iterated Sequences.
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EXAMPLE
| a(3)=102 because 102 is the least number with three direct predecessors, 66: 66+6*6 = 102, 74: 74+7*4 = 102, 101: 101+1*1 = 102.
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CROSSREFS
| Cf. A096972, A063108, A063425, A096922, A096923, A096924, A096925, A096926, A096927, A096928, A096929, A096930, A096931.
Sequence in context: A085389 A202013 A151505 * A137483 A113557 A123897
Adjacent sequences: A096344 A096345 A096346 * A096348 A096349 A096350
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KEYWORD
| base,more,nonn
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AUTHOR
| Jason Earls (zevi_35711(AT)yahoo.com), Jun 29 2004
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EXTENSIONS
| a(8) to a(11) from Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Jul 07 2004
a(12) from Robert G. Wilson v - Jul 15 2004
a(13)-a(19) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Nov 22 2009
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