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A006151 Number of Dyck paths.
(Formerly M4288)
3
1, 1, 6, 91, 2548, 111384, 6852768, 553361016, 55804330152, 6774025632340, 962310111888300, 156490840602392625, 28622389306817092500, 5804104057179375825000, 1289547073500366035700000 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

COMMENTS

a(n) is the determinant of the 5X5 Hankel matrix [a_0, a_1, a_2, a_3, a_4 ; a_1, a_2, a_3, a_4, a_5 ; a_2, a_3, a_4, a_5, a_6 ; a_3, a_4, a_5, a_6, a_7 ; a_4, a_5, a_6, a_7, a_8] with a_j=A000108(n+j) . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Apr 12 2007

REFERENCES

S. J. Cyvin and I. Gutman, Kekule structures in benzenoid hydrocarbons, Lecture Notes in Chemistry, No. 46, Springer, New York, 1988 (see p. 183).

M. de Sainte-Catherine, Couplages et Pfaffiens en Combinatoire. Physique et Informatique. Ph.D Dissertation, Universit\'{e} Bordeaux I, 1983.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

MAPLE

with (linalg): ctln:= proc(n) option remember; binomial (2*n, n)/ (n+1) end: a:= n-> det (Matrix(5, (i, j)-> ctln (i+j-2+n))): seq (a(n), n=0..20); [From Alois P. Heinz (heinz(AT)hs-heilbronn.de), Sep 10 2008]

CROSSREFS

Sequence in context: A013297 A077370 A095864 * A005327 A171910 A113266

Adjacent sequences:  A006148 A006149 A006150 * A006152 A006153 A006154

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

More terms from Alois P. Heinz (heinz(AT)hs-heilbronn.de), Sep 10 2008

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Last modified February 16 04:47 EST 2012. Contains 205860 sequences.