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A122025
a(n) = (3*a(n-1)*a(n-4) - a(n-2)*a(n-3)) / a(n-5).
1
1, 1, 1, 1, 1, 2, 5, 13, 29, 109, 629, 4274, 23329, 170353, 2034385, 35152177, 494532481, 7768108946, 176258003381, 7248370100941, 266967020984381, 9997125891977197, 431397731193035525, 38079906742644329378
OFFSET
0,6
MATHEMATICA
a[n_] := a[n] = (3*a[n - 1]a[n - 4] - a[n - 2]*a[n - 3])/a[n - 5]; a[0] = 1; a[1] = 1; a[2] = 1; a[3] = 1; a[4] = 1; Table[a[n], {n, 0, 30}]
RecurrenceTable[{a[1]==a[2]==a[3]==a[4]==a[5]==1, a[n]==(3a[n-1]a[n-4]-a[n-2]a[n-3])/a[n-5]}, a, {n, 30}] (* Harvey P. Dale, Sep 02 2017 *)
CROSSREFS
Cf. A006722.
Sequence in context: A242080 A178444 A299145 * A236414 A057873 A116699
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Sep 13 2006
EXTENSIONS
Edited by N. J. A. Sloane, Sep 17 2006
STATUS
approved