A332926 2*a(n) are the perimeters of distinct triangles with integer sides i <= j <= k, whose area equals 6 times their perimeter. Terms occurring more than once belong to different triangles.

63, 64, 65, 68, 70, 70, 72, 77, 77, 80, 81, 82, 84, 85, 88, 90, 91, 93, 95, 99, 105, 108, 110, 112, 112, 115, 117, 125, 126, 126, 128, 135, 136, 140, 143, 145, 152, 152, 153, 154, 160, 165, 168, 174, 180, 182, 182, 187, 198, 203, 203, 203, 205, 205, 208, 217

Offset: 1

Author

Hugo Pfoertner, Mar 02 2020

Keywords

• nonn
• fini
• full

Comments

There are A007237(6) = 139 integer-sided triangles with 6*area = perimeter, with terms 70, 77, 112, 126, 152, 182, 205, 260, 513, and 798 corresponding to pairs, and terms 203 to triples of such triangles with different sides.

Links

• Hugo Pfoertner, Table of n, a(n) for n = 1..139

Crossrefs

The terms of A332879, divided by 12, are all terms of this sequence, but omitting distinct triangles with identical perimeters.

Cf. A007237, A289155, A289156.