A106506 Length of side common to the two angles, one being the double of the other, of a primitive integer-sided triangle, sorted on perimeter (A106499).

5, 7, 16, 9, 11, 33, 24, 13, 39, 15, 56, 32, 17, 51, 85, 19, 72, 57, 40, 95, 21, 120, 105, 23, 88, 69, 48, 115, 25, 161, 75, 27, 104, 175, 56, 135, 29, 208, 189, 87, 168, 145, 31, 120, 203, 93, 64, 261, 155, 33, 240, 217, 192, 279, 165, 35, 136, 231, 105, 320, 72, 37, 272

Offset

1,1

Links

Table of n, a(n) for n=1..63.

Formula

a(n) = A106501(n)^2 - A106500(n)^2.

Mathematica

sol[p_] := Solve[1 < r < s < 2 r && p == r s + s^2 && GCD[r, s] == 1, {r, s}, Integers];
Reap[For[p = 1, p <= 1000, p++, sp = sol[p]; If[sp =!= {}, Print[s^2 - r^2 /. sp[[1]]]; Sow[s^2 - r^2 /. sp[[1]]]]]][[2, 1]] (* Jean-François Alcover, Mar 07 2020 *)

Crossrefs

Cf. A106499-A106505, A106410, A106420, A106430.

Sequence in context: A120282 A132094 A082878 * A029649 A327251 A314367

Adjacent sequences: A106503 A106504 A106505 * A106507 A106508 A106509

Keyword

nonn

Author

Lekraj Beedassy, May 04 2005

Extensions

Extended by Ray Chandler, May 09 2005

Status

approved