

A075880


Position of the circles around (0,0) that contain record numbers of lattice points in the list of all circles around (0,0) that pass through lattice points, ordered by increasing radius.


3



0, 1, 4, 13, 30, 121, 362, 1232, 1584, 7121, 17548, 32649, 37603, 174926, 437750, 821432, 1198677, 5678338, 14335447, 27044791, 43735981, 209473053, 531787054, 1006745669, 2097411347, 8474384496, 10122355701
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OFFSET

1,3


COMMENTS

The first terms of this sequence were given by James Buddenhagen in a sci.math posting on May 05 2002 entitled "Circle with 3 lattice points"


LINKS



FORMULA

a(n) = k1 for which A001481(k) = A071383(n). lim n >infinity a(n) = k_LR * exp(n) / n^(1/2), where k_LR is the LandauRamanujan constant 0.764223653... (A064533)


EXAMPLE



CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS

Minor edits to adjust formula and example for changes to offset of related sequences by Ray Chandler, Jan 13 2012


STATUS

approved



