%I
%S 0,0,0,0,0,0,0,0,0,0,2,54,717,6836,53696,371464,2349981,13915712,
%T 78331106,423642906,2218481677,11313458780,56431232688,276253783984,
%U 1330866576164,6323282609184,29682658858324,137864087593740
%N Number of 1punctured staircase polygons (by perimeter) with a hole of perimeter 6.
%D Guttmann, A.J. et al., Punctured polygons and polyominoes on the square lattice, J. Physics A: Math. and Gen, 33 (9) (2000), 17351764.
%p gf := (1  26*x + 228*x^2  906*x^3 + 1709*x^4  1378*x^5 + 322*x^6)/(2*(1  4*x)^(5/2))  (32*x^6  404*x^5 + 815*x^4  586*x^3 + 182*x^2  24*x + 1)/(2*(1  4*x)^2): s := series(gf, x, 50): for i from 0 to 50 do printf(`%d,`,coeff(s,x,i)) od:
%K easy,nonn
%O 0,11
%A _James A. Sellers_, May 31 2000
