A046112 a(n) is smallest integral radius of circle centered at (0,0) having 8n-4 lattice points on its circumference; a(n)/2 is smallest half-integral radius circle centered at (1/2,0) having 4n-2 lattice points; a(n)/3 is smallest third-integral radius circle centered at (1/3,0) having 2n-1 lattice points.

1, 5, 25, 125, 65, 3125, 15625, 325, 390625, 1953125, 1625, 48828125, 4225, 1105, 6103515625, 30517578125, 40625, 21125, 3814697265625, 203125, 95367431640625, 476837158203125, 5525, 11920928955078125, 274625

Offset: 1

Author

Eric W. Weisstein

Keywords

• nonn

Links

• Ray Chandler, Table of n, a(n) for n = 1..1439 (a(1440) exceeds 1000 digits).
• Eric Weisstein's World of Mathematics, Circle Lattice Points
• Eric Weisstein's World of Mathematics, Pythagorean Triple

Crossrefs

Except for offset, same as A006339.

Cf. A046109, A046110, A046111, A000328.