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Search: id:A097156
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| A097156 |
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Least number that requires exactly n iterations of f(x) = reverse(x) - maxdigit(x) to reach zero. |
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+0
6
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| 1, 11, 16, 12, 15, 25, 36, 106, 104, 108, 197, 1009, 1022, 1052, 1091, 1073, 1801, 10004, 10005, 10051, 10062, 10071, 10083, 10081, 10092, 14991, 19982, 19991, 100092, 100192, 100282, 100191, 107991, 101973, 289101, 1000094, 1000084
(list; graph; listen)
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OFFSET
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1,2
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EXAMPLE
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a(5)=15 because 15 -> 46 -> 58 -> 77 -> 70 -> 0 takes five steps to reach zero.
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MATHEMATICA
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g[n_] := Block[{id = IntegerDigits[n]}, ie = FromDigits[ Reverse[id]] - Union[id][[ -1]]; If[ie == 89, 0, ie]]; h[n_] := Length[NestWhileList[g, n, UnsameQ, All]] - 2; Do[ a = h[n]; If[a < 51 && t[[a]] == 0, t[[a]] = n], {n, 10^6}] (from Robert G. Wilson v Aug 13 2004)
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CROSSREFS
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Cf. A097153, A097154, A097155, A097157, A097158.
Sequence in context: A147339 A147377 A147333 this_sequence A138791 A132990 A074197
Adjacent sequences: A097153 A097154 A097155 this_sequence A097157 A097158 A097159
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KEYWORD
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base,nonn
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AUTHOR
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Jason Earls (zevi_35711(AT)yahoo.com), Aug 01 2004
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EXTENSIONS
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More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Aug 13 2004
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