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 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 Table of n, a(n) for n=1..12. 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 Adjacent sequences: A067558 A067559 A067560 * A067562 A067563 A067564 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

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