The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A067561 Radii n of circles with integer radius that can approximately be squared integrally: the floor or ceiling of Pi*n^2 is an integer square. 1
1, 22, 167, 334, 4821, 328663, 657326, 18796631, 37593262, 56389893, 75186524, 1591338537 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
a(13) > 5*10^9. - Sean A. Irvine, Dec 19 2023
LINKS
EXAMPLE
Ceiling(Pi*22^2) = 39^2, so 22 is a term of the sequence.
MATHEMATICA
Do[m = Pi*i^2; r = IntegerQ[Sqrt[Floor[m]]]; s = IntegerQ[Sqrt[Ceiling[m]]]; If[r || s, Print[i]], {i, 1, 10^6}]
CROSSREFS
Sequence in context: A185859 A173393 A141306 * A223768 A224156 A223775
KEYWORD
nonn,more
AUTHOR
Joseph L. Pe, Jan 29 2002
EXTENSIONS
More terms from Jason Earls, May 19 2002
a(12) from Sean A. Irvine, Dec 19 2023
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 28 12:54 EDT 2024. Contains 372913 sequences. (Running on oeis4.)