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A086949
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Numbers k such that reverse(k+9) = 5.
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3
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41, 491, 4991, 49991, 499991, 4999991, 49999991, 499999991, 4999999991, 49999999991, 499999999991, 4999999999991, 49999999999991, 499999999999991, 4999999999999991, 49999999999999991, 499999999999999991, 4999999999999999991, 49999999999999999991, 499999999999999999991
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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a(n) = 5*10^n - 9.
O.g.f.: x*(41 + 40*x)/((1 - x)*(1 - 10*x)).
E.g.f.: 4 - 9*exp(x) + 5*exp(10*x).
a(n) = 11*a(n-1) - 10*a(n-2) for n > 2. (End)
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MATHEMATICA
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PROG
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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