A219728
Squares of the form x^3 + 2*y^3, with x, y > 0.
Original entry on oeis.org
81, 5041, 5184, 10000, 46225, 59049, 77841, 83521, 322624, 331776, 640000, 685584, 707281, 1265625, 2958400, 3157729, 3418801, 3674889, 3779136, 4157521, 4981824, 5345344, 5602689, 5736025, 7290000, 9150625, 9529569, 10725625, 12257001, 14776336, 15904144
Offset: 1
81: (x = 3, y = 3), 5041: (x = 17, y = 4).
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With[{nn=300},Select[Flatten[Table[x^3+2y^3,{x,nn},{y,nn}]],IntegerQ[ Sqrt[#]]&]//Union] (* Harvey P. Dale, Oct 24 2018 *)
A219783
Smallest integer expressible as x^3 + 2*y^3 (x, y > 0) in exactly n ways.
Original entry on oeis.org
3, 1459, 314953199, 575012796875
Offset: 1
3: (x, y) = (1, 1)
1459: (x,y) = (1,9), (11,4)
314953199: (x,y) = (121, 539), (463, 476), (649, 275)
575012796875: (x, y) = (275, 6600), (6413, 5379), (7225, 4625), (8195, 2310)
A219784
Integers expressible as x^3 + 2*y^3 (x, y > 0) exactly in three ways.
Original entry on oeis.org
314953199, 432015625, 924667442, 1664304379, 1953968750, 2519625592, 3456125000, 4600102375, 7397339536, 8503736373, 11664421875, 13314435032, 15631750000, 20157004736, 24966020934, 27649000000, 36800819000, 38000696086, 39369149875, 44936218233, 52757156250, 54001953125, 59178716288
Offset: 1
314953199: (x,y) = (121, 539), (463, 476), (649, 275).
Showing 1-3 of 3 results.
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