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A212345
Sequence of coefficients of x^(n-4) in marked mesh pattern generating function Q_{n,132}^(0,3,0,0)(x).
0
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
OFFSET
4,1
LINKS
S. Kitaev, J. Remmel and M. Tiefenbruck, Marked mesh patterns in 132-avoiding permutations I, arXiv preprint arXiv:1201.6243, 2012
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]); Simplify[Series[QQ3[t, x], {t, 0, 35}]] (* Robert Price, Jun 03 2012 *)
CROSSREFS
Sequence in context: A057373 A153185 A325450 * A086500 A022669 A107313
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, May 09 2012
EXTENSIONS
a(9) corrected by Robert Price, Jun 03 2012
a(10)-a(35) from Robert Price, Jun 03 2012
STATUS
approved