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1, 5, 19, 43, 77, 121, 175, 239, 313, 397, 491, 595, 709, 833, 967, 1111, 1265, 1429, 1603, 1787, 1981, 2185, 2399, 2623, 2857, 3101, 3355, 3619, 3893, 4177, 4471, 4775, 5089, 5413, 5747, 6091, 6445, 6809, 7183, 7567, 7961, 8365, 8779, 9203, 9637, 10081, 10535
G.f.: (1+2*x+7*x^2)/(1-x)^3. - _From _Vincenzo Librandi_, Jul 06 2012: (Start)
G.f.: (1+2*x+7*x^2)/(1-x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - _Vincenzo Librandi_, Jul 06 2012(End)
a(n) = 2*A005476(n) + 1. - Bruno Berselli, Jul 06 2012
E.g.f.: exp(x)*(1 + 4*x + 5*x^2). - Elmo R. Oliveira, Oct 31 2024
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(MAGMAMagma) [ 5*n^2-n+1: n in [0..50] ];
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Table[5n^2-n+1, {n, 0, 50}] (* or *) LinearRecurrence[{3, -3, 1}, {1, 5, 19}, 50] (* Harvey P. Dale, Aug 06 2022 *)
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(PARI) a(n)=5*n^2-n+1 \\ Charles R Greathouse IV, Jun 17 2017
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