A383251 Short leg of the unique primitive Pythagorean triple whose inradius is A000108(n) and such that its long leg and its hypotenuse are consecutive natural numbers.

3, 3, 5, 11, 29, 85, 265, 859, 2861, 9725, 33593, 117573, 416025, 1485801, 5348881, 19389691, 70715341, 259289581, 955277401, 3534526381, 13128240841, 48932534041, 182965127281, 686119227301, 2579808294649, 9723892802905, 36734706144305, 139067101832009

Offset: 0

Author

Miguel-Ángel Pérez García-Ortega, Apr 20 2025

Keywords

• nonn
• easy

Examples

			Triangles begin:
  n=0:      3,    4,    5;
  n=1:      3,    4,    5;
  n=2:      5,   12,   13;
  n=3:     11,   60,   61;
  ...
This sequences gives the first column.
		

Links

• Miguel-Ángel Pérez García-Ortega, El Libro de las Ternas Pitagóricas

Crossrefs

Cf. A000108 (inradius), A382114 (semiperimeter), A381483 (area), A386291 (long legs).

Formula

a(n) = 2 * A000108(n) + 1.