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A257414 Values of n such that there are exactly 7 solutions to x^2 - y^2 = n with x > y >= 0. 4
768, 1280, 1792, 2816, 3328, 3645, 4352, 4864, 5103, 5832, 5888, 7424, 7936, 8019, 9472, 9477, 10496, 11008, 12032, 12393, 13568, 13851, 14580, 15104, 15616, 16384, 16767, 17152, 18176, 18688, 20224, 20412, 21141, 21248, 22599, 22784, 24832, 25856, 26368 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Colin Barker, Table of n, a(n) for n = 1..120

EXAMPLE

768 is in the sequence because there are 7 solutions to x^2 - y^2 = 768, namely (x,y) = (28,4), (32,16), (38,26), (52,44), (67,61), (98,94), (193,191).

PROG

(PARI) is_A257414(n)={A034178(n)==7} \\ M. F. Hasler, Apr 22 2015

CROSSREFS

Cf. A257408-A257413, A257415-A257417.

Cf. A034178.

Sequence in context: A116301 A219225 A045082 * A179668 A219317 A281238

Adjacent sequences:  A257411 A257412 A257413 * A257415 A257416 A257417

KEYWORD

nonn

AUTHOR

Colin Barker, Apr 22 2015

STATUS

approved

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Last modified February 19 13:36 EST 2020. Contains 332044 sequences. (Running on oeis4.)