OFFSET
0,2
LINKS
Alois P. Heinz, Rows n = 0..200, flattened
Rigoberto Flórez, Leandro Junes, and José L. Ramírez, Further Results on Paths in an n-Dimensional Cubic Lattice, Journal of Integer Sequences, Vol. 21 (2018), Article 18.1.2.
Ran Pan, Problem 5, Project P.
FORMULA
G.f.: 1/(1-4*x-(y-1)*x^2).
EXAMPLE
1
4
15 1
56 8
209 46 1
780 232 12
2911 1091 93 1
10864 4912 592 16
40545 21468 3366 156 1
151316 91824 17784 8010 20
MAPLE
b:= proc(n, t) option remember; expand(`if`(n=0, 1,
add(b(n-1, i)*`if`(t=1 and i=2, x, 1), i=1..4)))
end:
T:= n-> (p-> seq(coeff(p, x, i), i=0..degree(p)))(b(n, 0)):
seq(T(n), n=0..12); # Alois P. Heinz, Aug 29 2015
MATHEMATICA
CoefficientList[#, y]& /@ CoefficientList[1/(1-4x-(y-1)x^2) + O[x]^13, x] // Flatten (* Jean-François Alcover, Jan 10 2023 *)
CROSSREFS
KEYWORD
easy,nonn,tabf
AUTHOR
Ran Pan, Aug 29 2015
STATUS
approved