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A122055 A Somos 9 type recursion:a(n) = (3*a(n - 1)a(n - 8) - a(n - 4)*a(n - 5))/a(n - 9). 0
1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 5, 14, 41, 121, 353, 989, 2393, 9397, 49121, 342793, 2842633, 24619238, 211654405, 1731275594, 11581792513, 107195509553, 1126517154817, 16124559341513, 342648008481505, 8465982933121657, 213444061953471233 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,10

LINKS

Table of n, a(n) for n=1..31.

FORMULA

a(n) = (3*a(n - 1)a(n - 8) - a(n - 4)*a(n - 5))/a(n - 9)

MATHEMATICA

a[n_] := a[n] = (3*a[n - 1]a[n - 8] - a[n - 4]*a[n - 5])/a[n - 9]; a[0] = 1; a[1] = 1; a[2] = 1; a[3] = 1; a[4] = 1; a[5] = 1; a[6] = 1; a[7] = 1; a[8] = 1; Table[a[n], {n, 0, 30}]

CROSSREFS

Cf. A006731.

Sequence in context: A116850 A116847 A116848 * A116845 A116849 A123183

Adjacent sequences:  A122052 A122053 A122054 * A122056 A122057 A122058

KEYWORD

nonn,uned

AUTHOR

Roger L. Bagula, Sep 13 2006

STATUS

approved

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Last modified April 23 19:18 EDT 2014. Contains 240946 sequences.