A238240 Positive integers n such that x^2 - 20xy + y^2 + n = 0 has integer solutions.

18, 63, 72, 74, 83, 90, 99, 107, 162, 171, 227, 252, 288, 296, 315, 332, 347, 359, 360, 362, 387, 396, 407, 428, 450, 491, 495, 567, 626, 648, 666, 684, 711, 743, 747, 794, 810, 827, 842, 855, 866, 882, 887, 891, 908, 954, 963, 1008, 1031, 1143, 1152, 1163

Offset

1,1

Links

Table of n, a(n) for n=1..52.

Example

63 is in the sequence because x^2 - 20xy + y^2 + 63 = 0 has integer solutions, for example (x, y) = (1, 16).

Crossrefs

Cf. A075839 (n = 18), A221763 (n = 63), A198947 (n = 90), A001085 (n = 99).

Cf. A031363, A084917, A237351, A237599, A237606, A237609, A237610, A236330, A236331.

Sequence in context: A090073 A327089 A016728 * A232385 A275155 A259634

Adjacent sequences: A238237 A238238 A238239 * A238241 A238242 A238243

Keyword

nonn

Author

Colin Barker, Feb 20 2014

Status

approved