OFFSET
0,2
COMMENTS
Except for 2, exponents e such that x^e-x+1 is reducible.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..2000
Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
FORMULA
G.f.: ( 1+46*x+25*x^2 ) / (1-x)^3. - R. J. Mathar, Mar 10 2011
a(n) = 24*A005449(n)+1. - Jean-Bernard François, Oct 12 2014
a(n) = 3*a(n-1)-3*a(n-2)+a(n-3). - Wesley Ivan Hurt, Oct 13 2014
Sum_{n>=0} 1/a(n) = A086727. - Amiram Eldar, Nov 16 2020
MAPLE
MATHEMATICA
Table[(6n+1)^2, {n, 0, 100}] (* or *)
CoefficientList[Series[(1 + 46*x + 25*x^2)/(1 - x)^3, {x, 0, 30}], x] (* Wesley Ivan Hurt, Oct 13 2014 *)
LinearRecurrence[{3, -3, 1}, {1, 49, 169}, 50] (* Harvey P. Dale, Feb 17 2023 *)
PROG
(Magma) [(6*n+1)^2: n in [0..60]]; // Vincenzo Librandi, May 04 2011
(PARI) a(n)=(6*n+1)^2 \\ Charles R Greathouse IV, Jun 17 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved