Number of triangles in a Star of David of size n.

Terms

a(0) =0a(1) =20a(2) =118a(3) =354a(4) =788a(5) =1480a(6) =2490a(7) =3878a(8) =5704a(9) =8028a(10) =10910a(11) =14410a(12) =18588a(13) =23504a(14) =29218a(15) =35790a(16) =43280a(17) =51748a(18) =61254a(19) =71858a(20) =83620a(21) =96600a(22) =110858a(23) =126454a(24) =143448a(25) =161900a(26) =181870a(27) =203418a(28) =226604a(29) =251488