A256465 Number of points in a circle of squared radius n, points on the circle counted half.

3, 7, 9, 11, 17, 21, 21, 23, 27, 33, 37, 37, 41, 45, 45, 47, 53, 59, 61, 65, 69, 69, 69, 69, 75, 85, 89, 89, 93, 97, 97, 99, 101, 105, 109, 111, 117, 121, 121, 125, 133, 137, 137, 137, 141, 145, 145, 145, 147, 155, 161, 165, 173, 177, 177, 177, 177, 181, 185

Offset

1,1

Links

Table of n, a(n) for n=1..59.

S. W. P. Steen, An expression for the number of lattice-points in a circle, Q. J. Math. 1 (1930) 232-235.

Formula

a(n) = A057655(n) - A004018(n)/2.

Crossrefs

Cf. A057655, A004018.

Sequence in context: A186890 A248667 A075607 * A275386 A275602 A173699

Adjacent sequences: A256462 A256463 A256464 * A256466 A256467 A256468

Keyword

nonn,easy

Author

R. J. Mathar, Mar 30 2015

Status

approved