A022276 a(n) = n*(19*n - 1)/2.
0, 9, 37, 84, 150, 235, 339, 462, 604, 765, 945, 1144, 1362, 1599, 1855, 2130, 2424, 2737, 3069, 3420, 3790, 4179, 4587, 5014, 5460, 5925, 6409, 6912, 7434, 7975, 8535, 9114, 9712, 10329, 10965, 11620, 12294, 12987, 13699, 14430, 15180, 15949, 16737, 17544, 18370
Offset: 0
Links
- G. C. Greubel, Table of n, a(n) for n = 0..5000
- Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
Programs
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Magma
[n*(19*n - 1)/2: n in [0..45]]; // Vincenzo Librandi, Mar 31 2015
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Mathematica
Table[n (19 n - 1)/2, {n, 0, 40}] (* Bruno Berselli, Mar 12 2015 *) CoefficientList[Series[x (9 + 10 x) / (1 - x)^3, {x, 0, 40}], x] (* Vincenzo Librandi, Mar 31 2015 *) LinearRecurrence[{3,-3,1},{0,9,37},50] (* Harvey P. Dale, Jul 25 2021 *)
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PARI
a(n)=n*(19*n-1)/2 \\ Charles R Greathouse IV, Jun 17 2017
Formula
a(n) = 19*n + a(n-1) - 10 for n>0, a(0)=0. - Vincenzo Librandi, Aug 04 2010
From Vincenzo Librandi, Mar 31 2015: (Start)
G.f.: x*(9 + 10*x)/(1 - x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>2. (End)
a(n) = A022277(-n). - Bruno Berselli, Apr 01 2015
E.g.f.: (x/2)*(19*x + 18)*exp(x). - G. C. Greubel, Aug 23 2017
Extensions
More terms from Vincenzo Librandi, Mar 31 2015