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A075880
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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.
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3
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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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internal format)
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OFFSET
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1,3
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COMMENTS
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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"
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LINKS
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FORMULA
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a(n) = k-1 for which A001481(k) = A071383(n). lim n ->infinity a(n) = k_LR * exp(n) / n^(1/2), where k_LR is the Landau-Ramanujan constant 0.764223653... (A064533)
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EXAMPLE
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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Minor edits to adjust formula and example for changes to offset of related sequences by Ray Chandler, Jan 13 2012
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STATUS
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approved
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