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A225523
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Number of distinct products i*j over all pairs (i,j) with |i| + |j| <= n.
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2
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1, 1, 3, 5, 9, 11, 17, 21, 27, 33, 39, 43, 53, 59, 69, 79, 89, 97, 107, 117, 131, 143, 157, 167, 183, 195, 209, 223, 237, 249, 269, 283, 301, 317, 335, 353, 373, 389, 409, 427, 449, 465, 491, 509, 535, 557, 581, 603, 631, 657, 679
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OFFSET
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0,3
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COMMENTS
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This sequence is in reply to an extension request made in A100449.
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LINKS
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MATHEMATICA
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f[n_]:=Length[Complement[Union[Flatten[Table[If[Abs[i]+Abs[j]<=n, {i*j}], {i, -n, n}, {j, -n, n}], 1]], {Null}]]; Table[f[n], {n, 0, 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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