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%I #33 Feb 16 2019 01:10:48
%S 129,134,146,153,161,171,189,198,201,234,243,246,249,251,254,257,261,
%T 270,278,285,290,293,294,299,339,353,362,363,365,371,378,387,390,393,
%U 395,405,406,409,411,417,429,451,454,465,467,469,473,477,485,501,502,510,514,516
%N Numbers that are the sum of 3 nonzero squares in exactly 4 ways.
%H David A. Corneth, <a href="/A025324/b025324.txt">Table of n, a(n) for n = 1..1705</a> (first 593 terms from Robert Price, terms <= 2*10^6)
%H David A. Corneth, <a href="/A025324/a025324.gp.txt">Terms below (inclusive) 2*10^6 with the sums of squares</a>
%H David A. Corneth, <a href="/A025324/a025324_1.gp.txt">PARI program</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SquareNumber.html">Square Number.</a>
%H <a href="/index/Su#ssq">Index entries for sequences related to sums of squares</a>
%e 299 is a term because 299 = 1^2 + 3^2 + 17^2 = 3^2 + 11^2 + 13^2 = 5^2 + 7^2 + 15^2 = 7^2 + 9^2 + 13^2 and there are no more such sums of four nonzero squares giving 182. - _David A. Corneth_, Feb 13 2019
%t Select[Range@ 600, Length@ # == 4 &@ DeleteCases[PowersRepresentations[#, 3, 2], _?(AnyTrue[#, # == 0 &] &)] &] (* _Michael De Vlieger_, Feb 13 2019 *)
%o (PARI) \\ See Corneth link \\ _David A. Corneth_, Feb 13 2019
%Y Cf. A024796, A025427, A025322, A025323, A025324, A025325, A025326, A025327, A025328, A025329, A025330, A025331, A025332, A025333, A025334, A025335, A025336, A025337, A025338.
%K nonn
%O 1,1
%A _David W. Wilson_
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