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A143131
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Binomial transform of [1, 4, 10, 20, 0, 0, 0, ...].
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0
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1, 5, 19, 63, 157, 321, 575, 939, 1433, 2077, 2891, 3895, 5109, 6553, 8247, 10211, 12465, 15029, 17923, 21167, 24781, 28785, 33199, 38043, 43337, 49101, 55355, 62119, 69413, 77257, 85671, 94675, 104289, 114533, 125427, 136991, 149245
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OFFSET
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1,2
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LINKS
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FORMULA
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Binomial transform of [1, 4, 10, 20, 0, 0, 0, ...], where (1, 4, 10, 20) = row 3 of triangle A046899
a(n) = (-39 + 77*n - 45*n^2 + 10*n^3)/3. - T. D. Noe, Aug 22 2008
G.f.: x*(1+x+5*x^2+13*x^3)/(1-x)^4. - Colin Barker, Mar 23 2012
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EXAMPLE
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a(4) = 63 = (1, 3, 3, 1) dot (1, 4, 10, 20) = (1 + 12 + 30 + 20).
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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