The On-Line Encyclopedia of Integer Sequences (OEIS)

A212345 revision #14

A212345

Sequence of coefficients of x^(n-4) in marked mesh pattern generating function Q_{n,132}^(0,3,0,0)(x).

9, 18, 45, 126, 378, 1188, 3861, 12870, 43758, 151164, 529074, 1872108, 6686100, 12034980, 87253605, 318219030, 1166803110, 4298748300, 15905368710, 59077083780, 220196403180, 823343072760, 3087536522850, 11609137325916, 43757517613068, 165306177649368, 625801958244036, 2373731565753240, 9020179949862312, 34334878518830736, 130901724353042181, 499806583893433782

(list; graph; refs; listen; history; text; internal format)

OFFSET

4,1

REFERENCES

S. Kitaev, J. Remmel and M. Tiefenbruck, Marked mesh patterns in 132-avoiding permutations I, Arxiv preprint arXiv:1201.6243, 2012.

LINKS

Table of n, a(n) for n=4..35.

MATHEMATICA

QQ0[t, x] = (1 - (1-4*x*t)^(1/2)) ) / (2*x*t);

QQ1[t, x] = 1/(1 - t*QQ0[t, x]);

QQ2[t, x] = (1 + t*(QQ1[t, x] - QQ0[t, x]))/(1 - t*QQ0[t, x]);

QQ3[t, x] = (1 + t*(QQ2[t, x] - QQ0[t, x] + t*(QQ1[t, x] - QQ0[t, x])))/(1 - t*QQ0[t, x]);