OFFSET
0,2
COMMENTS
Note: a 0 step counts as a visit and a step but does not contribute to the length of the walk.
FORMULA
G.f. (-1-2*x-2*x^2-2*x^3+2*x^4-2*x^5-2*x^6-2*x^7+3*x^8) / ((-1+x^2)^2 * (-1+2*x+x^4)).
MATHEMATICA
CoefficientList[Series[ (-1-2*x-2*x^2-2*x^3+2*x^4-2*x^5-2*x^6 -2*x^7+3*x^8)/((-1+x^2)^2 * (-1+2*x+x^4)), {x, 0, 45}], x]
CROSSREFS
KEYWORD
nonn,walk
AUTHOR
David Scambler, May 22 2012
STATUS
approved