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A291893
Number of symmetrically unique Dyck paths of semilength n and height nine.
2
1, 9, 89, 639, 4082, 23191, 122381, 607944, 2887756, 13229876, 58898404, 256121253, 1092452270, 4585149401, 18985099139, 77707979700, 314944855135, 1265638606115, 5048705160315, 20010229736469, 78861912700117, 309252947330313, 1207359268831473
OFFSET
9,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (18, -129, 428, -339, -2154, 7022, -5004, -13608, 31128, -13587, -27364, 38529, -11230, -11610, 11180, -3805, 550, -25).
FORMULA
G.f.: -x^9*(-1+9*x-56*x^2+230*x^3-548*x^4+741*x^5-564*x^6+238*x^7-55*x^8+5*x^9) / ((x^2-3*x+1) *(5*x^2-5*x+1) *(5*x^4-5*x^2+1) *(x^5-3*x^4-3*x^3+4*x^2+x-1) *(x^5-15*x^4+35*x^3-28*x^2+9*x-1)).
CROSSREFS
Column k=9 of A291883.
Sequence in context: A055410 A214616 A175371 * A217321 A111918 A064616
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Sep 05 2017
STATUS
approved