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A173808
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(7*10^n+11)/9 for n>0.
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1
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9, 79, 779, 7779, 77779, 777779, 7777779, 77777779, 777777779, 7777777779, 77777777779, 777777777779, 7777777777779, 77777777777779, 777777777777779, 7777777777777779, 77777777777777779, 777777777777777779
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OFFSET
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1,1
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LINKS
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Vincenzo Librandi, Table of n, a(n) for n = 1..100
Index to sequences with linear recurrences with constant coefficients, signature (11,-10).
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FORMULA
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a(n) = 10*a(n-1)-11 with n>0, a(0)=2.
G.f.: x*(9-20*x)/((1-x)*(1-10*x)). - Vincenzo Librandi Jul 05 2012
a(n) = 11*a(n-1) -10*a(n-2). - Vincenzo Librandi, Jul 05 2012
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MATHEMATICA
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CoefficientList[Series[(9-20*x)/((1-x)*(1-10*x)), {x, 0, 30}], x] (* Vincenzo Librandi, Jul 05 2012 *)
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PROG
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(MAGMA) [(7*10^n+11)/9: n in [1..20]]; // Vincenzo Librandi Jul 05 2012
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CROSSREFS
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Cf. A093404.
Sequence in context: A190979 A083411 A181279 * A171314 A081108 A176174
Adjacent sequences: A173805 A173806 A173807 * A173809 A173810 A173811
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KEYWORD
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nonn,easy
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AUTHOR
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Vincenzo Librandi, Feb 25 2010
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STATUS
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approved
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