A027599 a(n) = 3*n^2 - 7*n + 6.
6, 2, 4, 12, 26, 46, 72, 104, 142, 186, 236, 292, 354, 422, 496, 576, 662, 754, 852, 956, 1066, 1182, 1304, 1432, 1566, 1706, 1852, 2004, 2162, 2326, 2496, 2672, 2854, 3042, 3236, 3436, 3642, 3854, 4072, 4296, 4526, 4762, 5004, 5252, 5506
Offset: 0
References
- Encyclopaedia Britannica, 1965 ed., Vol. 16 pp. 755-756.
Links
- G. C. Greubel, Table of n, a(n) for n = 0..1000
- Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
Crossrefs
Cf. A049450.
Programs
-
Magma
[((6*n-7)^2+23)/12: n in [0..60]]; // G. C. Greubel, Aug 24 2022
-
Mathematica
LinearRecurrence[{3,-3,1}, {6,2,4}, 61] (* G. C. Greubel, Aug 24 2022 *) -
PARI
a(n)=3*n^2-7*n+6 \\ Charles R Greathouse IV, Jun 17 2017
-
SageMath
[3*n^2-7*n+6 for n in (0..60)] # G. C. Greubel, Aug 24 2022
Formula
a(n) = a(n-1) + 6*n - 10 (with a(0)=6). - Vincenzo Librandi, Nov 19 2010
From Colin Barker, May 22 2012: (Start)
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3).
G.f.: 2*(3 - 8*x + 8*x^2)/(1 - x)^3. (End)
E.g.f.: (6 - 4*x + 3*x^2)*exp(x). - G. C. Greubel, Aug 24 2022