OFFSET
2,1
COMMENTS
3 followed by the positive even integers starting with 4. - Wesley Ivan Hurt, Feb 09 2014
REFERENCES
Peter Hayes, A Problem of Chess Queens, Journal of Recreational Mathematics, 24(4), 1992, 264-271.
LINKS
Colin Barker, Table of n, a(n) for n = 2..1000
Index entries for linear recurrences with constant coefficients, signature (2,-1).
FORMULA
a(2) = 3, a(n) = 2n-2 for n >= 3.
a(n) = 2*a(n-1)-a(n-2) for n>4. - Colin Barker, Nov 08 2014
G.f.: x^2*(x^2-2*x+3) / (x-1)^2. - Colin Barker, Nov 08 2014
MAPLE
MATHEMATICA
CoefficientList[Series[(z^2 - 2*z + 3)/(z - 1)^2, {z, 0, 100}], z] (* and *) Join[{3}, Table[2*n, {n, 2, 200}]] (* Vladimir Joseph Stephan Orlovsky, Jul 10 2011 *)
LinearRecurrence[{2, -1}, {3, 4, 6}, 70] (* Harvey P. Dale, Aug 29 2017 *)
PROG
(PARI) Vec(x^2*(x^2-2*x+3)/(x-1)^2 + O(x^100)) \\ Colin Barker, Nov 08 2014
CROSSREFS
KEYWORD
nonn,nice,easy
AUTHOR
Robert Trent (trentrd(AT)hotmail.com), Aug 23 2000
EXTENSIONS
More terms from Jud McCranie, Aug 11 2001
STATUS
approved