OFFSET
0,3
LINKS
Philippe Flajolet, A seating arrangement problem. See page 11.
Philippe Flajolet, A seating arrangement problem [Cached copy]. See page 11.
Dave Freedman and Larry Shepp, An unfriendly seating arrangement, Problem 62-3, SIAM Review, Vol. 6 (1964), 180-182.
MAPLE
gb:=proc(n, b) local k; option remember;
if n<=0 then 1 elif n<=b then u else expand(u/n*convert([seq(gb(k-b-1, b)*gb(n-k-b, b), k=1..n)], `+`))
fi
end:
l3:=subs(u=1, diff([seq(gb(j, 2), j=0..25)], u));
[seq(l3[i]*(i-1)!, i=1..26)];
MATHEMATICA
g[n_, b_] := g[n, b] = Which[n <= 0, 1, n <= b, u, True, u/n Sum[g[k-b-1, b] g[n-k-b, b], {k, 1, n}]];
D[Table[g[j, 2] j!, {j, 0, 25}], u] /. u -> 1 (* Jean-François Alcover, Jul 29 2018, from Maple *)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Mar 29 2014
STATUS
approved