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A225527
Number of distinct products i*j over all pairs (i,j) with i,j>=0 and i+j <= n.
2
1, 1, 2, 3, 5, 6, 9, 11, 14, 17, 20, 22, 27, 30, 35, 40, 45, 49, 54, 59, 66, 72, 79, 84, 92, 98, 105, 112, 119, 125, 135, 142, 151, 159, 168, 177, 187, 195, 205, 214, 225, 233, 246, 255, 268, 279, 291, 302, 316, 329, 340, 352, 367, 377, 392
OFFSET
0,3
COMMENTS
This sequence is in reply to an extension request made in A100449.
LINKS
MATHEMATICA
f[n_]:=Length[Complement[Union[Flatten[Table[If[i+j≤n, {i*j}], {i, 0, n}, {j, 0, n}], 1]], {Null}]]; Table[f[n], {n, 0, 100}]
KEYWORD
nonn,easy
AUTHOR
Robert Price, May 09 2013
STATUS
approved