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%I #21 Dec 30 2019 10:14:26
%S 1105,1885,2210,2405,2465,2665,3145,3315,3445,3485,3770,3965,4420,
%T 4505,4745,4810,4930,5185,5330,5365,5655,5785,5945,6205,6290,6305,
%U 6409,6565,6630,6890,6970,7085,7215,7345,7395,7540,7565,7585,7685,7735,7930,7995
%N Numbers n that are the hypotenuse of exactly 13 distinct integer-sided right triangles, i.e., n^2 can be written as a sum of two squares in 13 ways.
%C If m is a term, then 2*m and p*m are terms where p is any prime of the form 4k+3. - _Ray Chandler_, Dec 30 2019
%H Chai Wah Wu, <a href="/A097102/b097102.txt">Table of n, a(n) for n = 1..10000</a>
%t r[a_]:={b, c}/.{ToRules[Reduce[0<b<c&&a^2 == b^2 + c^2, {b, c}, Integers]]}; Select[Range[5000], Length[r[#]] == 13 &] (* _Vincenzo Librandi_, Mar 01 2016 *)
%Y Cf. A004144 (0), A084645 (1), A084646 (2), A084647 (3), A084648 (4), A084649 (5), A097219 (6), A097101 (7), A290499 (8), A290500 (9), A097225 (10), A290501 (11), A097226 (12), A290502 (14), A290503 (15), A097238 (16), A097239 (17), A290504 (18), A290505 (19), A097103 (22), A097244 (31), A097245 (37), A097282 (40), A097626 (67).
%K nonn
%O 1,1
%A _James R. Buddenhagen_, Sep 15 2004
%E More terms from _Ray Chandler_, Sep 16 2004
%E Definition corrected by _Zak Seidov_, Feb 26 2008
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