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A293403
Greatest integer k such that k/n^2 < (3 + sqrt(5))/2.
4
0, 2, 10, 23, 41, 65, 94, 128, 167, 212, 261, 316, 376, 442, 513, 589, 670, 756, 848, 945, 1047, 1154, 1267, 1384, 1507, 1636, 1769, 1908, 2052, 2201, 2356, 2515, 2680, 2851, 3026, 3207, 3392, 3584, 3780, 3982, 4188, 4400, 4618, 4840, 5068, 5301, 5539, 5783
OFFSET
0,2
LINKS
FORMULA
a(n) = floor(r*n^2), where r = (3 + sqrt(5))/2.
a(n) = A293404(n) - 1 for n > 0.
MATHEMATICA
z = 120; r = 1+GoldenRatio;
Table[Floor[r*n^2], {n, 0, z}]; (* A293403 *)
Table[Ceiling[r*n^2], {n, 0, z}]; (* A293404 *)
Table[Round[r*n^2], {n, 0, z}]; (* A293405 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Oct 11 2017
STATUS
approved