OFFSET
0,2
COMMENTS
LINKS
Alois P. Heinz, Rows n = 0..250, flattened
FORMULA
G.f.: G(t,z) = (1+(1-t)z^3)/(1 - 2z + (1-t)(1-z)z^3).
EXAMPLE
T(8,2) = 5 because we have 01100110, 01101100, 01101101, 00110110 and 10110110.
Triangle starts:
1;
2;
4;
8;
15, 1;
28, 4;
52, 12;
97, 30, 1;
181, 70, 5;
338, 156, 18;
631, 339, 53, 1;
MAPLE
G:=(1+(1-t)*z^3)/(1-2*z+(1-t)*(1-z)*z^3): Gser:=simplify(series(G, z=0, 24)): P[0]:=1: for n from 1 to 18 do P[n]:=sort(coeff(Gser, z^n)) od: 1; for n from 1 to 18 do seq(coeff(P[n], t, j), j=0..ceil(n/3)-1) od; # yields sequence in triangular form
MATHEMATICA
nn=18; c=x^3; Map[Select[#, #>0&]&, CoefficientList[Series[1/(1-2x - (y-1)x^4/ (1-(y-1)c)), {x, 0, nn}], {x, y}]]//Flatten (* Geoffrey Critzer, Dec 25 2013 *)
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Emeric Deutsch, May 04 2006
STATUS
approved