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A166381
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a(n) = Sum_{j>n} floor(n^2/j).
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2
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0, 2, 7, 17, 31, 52, 76, 108, 146, 191, 242, 301, 364, 437, 518, 605, 700, 804, 914, 1034, 1160, 1295, 1438, 1594, 1751, 1921, 2098, 2288, 2483, 2688, 2898, 3119, 3350, 3593, 3845, 4103, 4369, 4647, 4937, 5234, 5540, 5854, 6178, 6512, 6859
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OFFSET
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1,2
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LINKS
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FORMULA
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MAPLE
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add( floor(n^2/j), j=n+1..n^2) ;
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MATHEMATICA
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Table[Sum[Floor[n (n - i)/i], {i, n}], {n, 100}]
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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