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A139620
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a(n) = 190*n + 20.
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5
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20, 210, 400, 590, 780, 970, 1160, 1350, 1540, 1730, 1920, 2110, 2300, 2490, 2680, 2870, 3060, 3250, 3440, 3630, 3820, 4010, 4200, 4390, 4580, 4770, 4960, 5150, 5340, 5530, 5720, 5910, 6100, 6290, 6480, 6670, 6860, 7050, 7240, 7430
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OFFSET
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0,1
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COMMENTS
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Numbers of the 20th column of positive numbers in the square array of nonnegative and polygonal numbers A139600. Also, numbers of the 20th column in the square array A057145.
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LINKS
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FORMULA
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G.f.: 10*(2+17*x)/(x-1)^2.
E.g.f.: 10*exp(x)*(2 + 19*x).
a(n) = 2*a(n-1) - a(n-2) for n >= 2. (End)
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MATHEMATICA
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190*Range[0, 40]+20 (* or *) LinearRecurrence[{2, -1}, {20, 210}, 40] (* Harvey P. Dale, Feb 04 2019 *)
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PROG
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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