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A257412 Values of n such that there are exactly 5 solutions to x^2 - y^2 = n with x > y >= 0. 4
144, 192, 225, 320, 400, 405, 441, 448, 567, 648, 704, 784, 832, 891, 900, 1024, 1053, 1088, 1089, 1216, 1225, 1377, 1472, 1521, 1539, 1620, 1764, 1856, 1863, 1875, 1936, 1984, 2048, 2268, 2349, 2368, 2511, 2601, 2624, 2704, 2752, 2997, 3008, 3025, 3249 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Colin Barker, Table of n, a(n) for n = 1..150

EXAMPLE

144 is in the sequence because there are 5 solutions to x^2 - y^2 = 144, namely (x,y) = (12,0), (13,5), (15,9), (20,16), (37,35).

PROG

(PARI) is_A257412(n)={A034178(n)==5} \\ M. F. Hasler, Apr 22 2015

CROSSREFS

Cf. A257408-A257411, A257413-A257417.

Cf. A034178.

Sequence in context: A156316 A323614 A245214 * A165076 A165078 A135780

Adjacent sequences:  A257409 A257410 A257411 * A257413 A257414 A257415

KEYWORD

nonn

AUTHOR

Colin Barker, Apr 22 2015

STATUS

approved

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Last modified December 13 22:48 EST 2019. Contains 329974 sequences. (Running on oeis4.)