A120961 Composite hypotenuses of primitive Pythagorean triangles.

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

Ray Chandler, Table of n, a(n) for n = 1..10000

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

Cf. A120960, A008846, A146945, A024409.

Sequence in context: A183373 A354381 A306358 * A285579 A050993 A121387

Adjacent sequences: A120958 A120959 A120960 * A120962 A120963 A120964

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