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A120961
Composite hypotenuses of primitive Pythagorean triangles.
4
25, 65, 85, 125, 145, 169, 185, 205, 221, 265, 289, 305, 325, 365, 377, 425, 445, 481, 485, 493, 505, 533, 545, 565, 625, 629, 685, 689, 697, 725, 745, 785, 793, 841, 845, 865, 901, 905, 925, 949, 965, 985, 1025, 1037, 1073, 1105, 1145, 1157, 1165, 1189, 1205
OFFSET
1,1
COMMENTS
Composite entries of A008846. Disjoint union of A024409 and A146945.
LINKS
César Aguilera, On Pythagorean Triples, hal-02151737 preprint [math.NT], 2019.
MATHEMATICA
lst = {}; Do[ If[ GCD[m, n] == 1, a = 2 m*n; b = m^2 - n^2; c = m^2 + n^2; If[ !PrimeQ@c, AppendTo[lst, c]]], {m, 3, 300}, {n, If[ OddQ@m, 2, 1], m - 1, 2}]; Take[ Union@ lst, 51] (* Robert G. Wilson v, May 02 2009 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Lekraj Beedassy, Jul 19 2006
EXTENSIONS
Term 485, which satisfies 485^2 = 476^2 + 93^2, added by Robert G. Wilson v, May 02 2009
STATUS
approved