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A071340
a(n) = least positive r <= n such that the origin-centered circle of radius sqrt(r) touches A071339(n) lattice points.
2
0, 1, 1, 5, 5, 25, 25, 25, 25, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 325, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105, 1105
OFFSET
0,4
EXAMPLE
a(4)=5 because the smallest circle to touch A071339(4)=8 points has radius sqrt(5).
PROG
(FORTRAN) See A071339.
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Hugo Pfoertner, May 22 2002
EXTENSIONS
Edited by Don Reble, Nov 06 2005
STATUS
approved