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A257417 Values of n such that there are exactly 10 solutions to x^2 - y^2 = n with x > y >= 0.

%I A257417 #20 Apr 24 2023 12:13:15
%S A257417 960,1344,1728,2112,2240,2496,2592,2835,3240,3264,3520,3648,4160,4416,
%T A257417 4455,4536,4928,5265,5440,5568,5824,5952,6080,6144,6237,6885,7104,
%U A257417 7128,7360,7371,7616,7695,7872,8000,8256,8424,8512,9024,9152,9280,9315,9639,9920
%N A257417 Values of n such that there are exactly 10 solutions to x^2 - y^2 = n with x > y >= 0.
%H A257417 David A. Corneth, <a href="/A257417/b257417.txt">Table of n, a(n) for n = 1..10000</a> (first 200 terms from Colin Barker)
%e A257417 960 is in the sequence because there are 10 solutions to x^2 - y^2 = 960, namely (x,y) = (31,1), (32,8), (34,14), (38,22), (46,34), (53,43), (64,56), (83,77), (122,118), (241,239).
%t A257417 nn = 10000;
%t A257417 t = Table[0, {nn}];
%t A257417 Do[n = x^2 - y^2; If[n <= nn, t[[n]]++], {x, nn}, {y, 0, x - 1}];
%t A257417 Position[t, 10] // Flatten (* _Jean-François Alcover_, Jun 18 2020, after _T. D. Noe_ in A034178 *)
%o A257417 (PARI) is_A257417(n)={A034178(n)==10} \\ _M. F. Hasler_, Apr 22 2015
%Y A257417 Cf. A257408, A257409, A257410, A257411, A257412, A257413, A257414, A257415, A257416.
%Y A257417 Cf. A034178.
%K A257417 nonn
%O A257417 1,1
%A A257417 _Colin Barker_, Apr 22 2015