%I #10 Sep 05 2018 10:34:22
%S 1,48,7680,1105920,1061683200,5662310400,1630745395200,
%T 391378894848000,50096498540544000,108208436847575040000,
%U 51940049686836019200000,831040794989376307200000,2393397489569403764736000000,22976615899866276141465600000
%N Denominators of mass formula for vacuum graphs for a phi^6 field theory.
%H C. M. Bender and K. A. Milton, <a href="http://arxiv.org/abs/hep-th/9304062">Continued fraction as a discrete nonlinear transform</a>, arXiv:hep-th/9304062, 1993. See V_n with N=3.
%e 1, 1/48, 77/7680, 17017/1105920, 52055003/1061683200, 1509595087/5662310400,
%e 3603403472669/1630745395200, 10151817126357907/391378894848000, ...
%t V[n_] := (6 n - 1)!!/(6!^n n!);
%t Table[V[n] // Denominator, {n, 0, 13}] (* _Jean-François Alcover_, Sep 05 2018 *)
%Y Cf. A226256, A225697, A225698.
%K nonn,frac
%O 0,2
%A _N. J. A. Sloane_, Jun 02 2013