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 A108126 Maximal number of squares of side 1 in an ellipse of semiaxes n,2n. 0
 3, 17, 43, 83, 137, 203, 279, 369, 471, 587, 715, 857, 1011, 1175, 1351, 1541, 1743, 1961, 2191, 2429, 2683, 2949, 3227, 3523, 3829, 4137, 4469, 4809, 5167, 5539, 5913, 6295, 6701, 7127, 7555, 7999, 8449, 8909, 9395, 9889, 10395, 10915 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(1)=3 since you cannot pack more than 3 unit-side squares in an ellipse of semiaxes 1,2 MATHEMATICA f[n_] := 2 Sum[IntegerPart[2 Sqrt[4 n^2 - (h - 1/2)^2]], {h, 2, 2 n}] + IntegerPart[2 Sqrt[4 n^2 - 1/4]]; Array[f, 42] CROSSREFS Similar to A125228. Sequence in context: A092347 A215429 A126587 * A106256 A091624 A106078 Adjacent sequences:  A108123 A108124 A108125 * A108127 A108128 A108129 KEYWORD easy,nonn AUTHOR Pasquale CUTOLO (p.cutolo(AT)inwind.it), Jun 14 2007 STATUS approved

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Last modified May 9 04:58 EDT 2021. Contains 343687 sequences. (Running on oeis4.)