OFFSET
0,3
COMMENTS
Paths are not required to be self-avoiding. - Andrew Howroyd, Nov 05 2019
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (18,-44,-168).
FORMULA
G.f.: (1 - 18*x + 58*x^2)/((1 + 2*x)*(1 - 6*x)*(1 - 14*x)).
a(n) = 18*a(n-1) - 44*a(n-2) - 168*a(n-3) for n >= 3. - Andrew Howroyd, Nov 05 2019
MATHEMATICA
CoefficientList[ Series[(1 - 18 x + 58 x^2)/((1 + 2 x) (1 - 6 x) (1 - 14 x)), {x, 0, 16}], x]
LinearRecurrence[{18, -44, -168}, {1, 0, 14}, 30] (* Harvey P. Dale, Feb 13 2023 *)
PROG
(PARI) Vec((1 - 18*x + 58*x^2)/((1 + 2*x)*(1 - 6*x)*(1 - 14*x)) + O(x^20)) \\ Andrew Howroyd, Nov 05 2019
CROSSREFS
KEYWORD
nonn,easy,walk
AUTHOR
EXTENSIONS
Terms a(17) and beyond from Andrew Howroyd, Nov 05 2019
STATUS
approved