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⇱ A097102 - OEIS

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A097102
Numbers m that are the hypotenuse of exactly 13 distinct integer-sided right triangles, i.e., m^2 can be written as a sum of two squares in 13 ways.
25
1105, 1885, 2210, 2405, 2465, 2665, 3145, 3315, 3445, 3485, 3770, 3965, 4420, 4505, 4745, 4810, 4930, 5185, 5330, 5365, 5655, 5785, 5945, 6205, 6290, 6305, 6409, 6565, 6630, 6890, 6970, 7085, 7215, 7345, 7395, 7540, 7565, 7585, 7685, 7735, 7930, 7995
OFFSET
1,1
COMMENTS
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
MATHEMATICA
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 *)
CROSSREFS
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).
Sequence in context: A025305 A025287 A052155 * A281877 A159781 A264498
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Ray Chandler, Sep 16 2004
Definition corrected by Zak Seidov, Feb 26 2008
STATUS
approved