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Positive numbers of the form x^5-10x^3*y^2+5x*y^4 (where x,y are integers and y>x).
5

%I #5 Apr 06 2015 10:44:15

%S 41,122,316,1121,1312,1900,2868,2876,3904,4282,6121,9963,10112,11516,

%T 17684,19841,20122,23028,23807,25525,29646,31996,35872,41984,44403,

%U 49001,59162,60800,65900,71996,76453,76788,80404,91776,92032

%N Positive numbers of the form x^5-10x^3*y^2+5x*y^4 (where x,y are integers and y>x).

%C Refers to A057102, which had an incorrect description and has been replaced by A256418. As a result the present sequence should be re-checked. - _N. J. A. Sloane_, Apr 06 2015

%t a = {}; Do[Do[w = x^5 - 10x^3 y^2 + 5x y^4; If[w > 0 && w < 100000, AppendTo[a, w]], {y, x, 1000}], {x, 1, 1000}]; Union[a]

%Y Cf. A000404, A050803, A057102, A135784, A060803, A135786, A135787, A135789, A135790, A135791, A135793.

%K nonn

%O 1,1

%A _Artur Jasinski_, Nov 29 2007