OFFSET
6,2
LINKS
S. Kitaev, J. Remmel and M. Tiefenbruck, Marked mesh patterns in 132-avoiding permutations I, arXiv preprint arXiv:1201.6243, 2012
MATHEMATICA
CCC[t] = (1 - (1 - 4*t)^(1/2))/(2*t); NQ0[t, x] = ((1 + t - t*x) - ((1 + t - t*x)^2 - 4*t)^(1/2))/(2*t); NQ1[t, x] = 1/(1 - t*NQ0[t, x]); NQ2[t, x] = 1/(1 - t*NQ1[t, x]); NQ3[t, x] = 1/(1 - t*NQ2[t, x]); NQ4[t, x] = 1/(1 - t*NQ3[t, x]); NQ5[t, x] = 1/(1 - t*NQ4[t, x]); CoefficientList[Coefficient[Simplify[Series[NQ5[t, x], {t, 0, 20}]], x], t] (* Robert Price, Jun 06 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert Price, Jun 06 2012
STATUS
approved