A089630 Size of the smallest n-cluster.

1, 1, 4, 6, 56, 1275

Offset

1,3

Comments

a(7) >= 20937. Points (x,y) of the smallest n-cluster for 1 < n < 7 : (0,0), (1,0); (0,0), (3,0), (0,4); (0,0), (3,4), (3,-4), (6,0); (0,0), (16,30), (-16,30), (0,-33), (56,0); (0,0), (546,272), (960,720), (132,720), (546,-1120), (1155,-540).

References

N. Fardin and B. Langlois, "Ensembles du plan à distances mutuelles rationnelles", Quadrature, 39 (2000), p. 23.

Links

Table of n, a(n) for n=1..6.

L. C. Noll and D. I. Bell, n-clusters for 1 < n < 7, Math. Comput., 53 (1989), pp. 439-444.

Crossrefs

Sequence in context: A259133 A131847 A351733 * A058162 A244388 A132929

Adjacent sequences: A089627 A089628 A089629 * A089631 A089632 A089633

Keyword

nonn,more

Author

Philippe Deléham, Jan 03 2004

Status

approved