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Search: id:A109867
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| A109867 |
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a(1) = 12; for n >= 1, a(n+1) = {a(n)+R(a(n)}*{a(n)-R(a(n)}. where R(k) is the digit reversal of k. |
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| 12, 297, 539055, 12949081200, 167631138529627443759, 888408727567955042239409874101472777521040, 787659989217062162749912989661115208857840881836480202901460330472578518132645989056
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OFFSET
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1,1
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EXAMPLE
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a(2) = {12+21)*(21-12) = 297.
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MATHEMATICA
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a = {12}; For[n = 2, n < 10, n++, AppendTo[a, Abs[(a[[ -1]] + FromDigits[Reverse[IntegerDigits[a[[ -1]]]]])* (a[[ -1]] - FromDigits[Reverse[IntegerDigits[a[[ -1]]]]])]]]; a - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Jun 05 2007
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CROSSREFS
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Sequence in context: A001164 A041267 A041264 this_sequence A014130 A054942 A052795
Adjacent sequences: A109864 A109865 A109866 this_sequence A109868 A109869 A109870
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KEYWORD
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base,nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Jul 09 2005
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EXTENSIONS
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Corrected and extended by Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Jun 05 2007
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