login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual Appeal: Today, Nov 11 2014, is the 4th anniversary of the launch of the new OEIS web site. 70,000 sequences have been added in these four years, all edited by volunteers. Please make a donation (tax deductible in the US) to help keep the OEIS running.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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 * A244885 A116845 A116849

Adjacent sequences:  A122052 A122053 A122054 * A122056 A122057 A122058

KEYWORD

nonn,uned

AUTHOR

Roger L. Bagula, Sep 13 2006

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified December 20 23:03 EST 2014. Contains 252290 sequences.