Number of scalene triangles on a centered hexagonal grid of size n.

Terms

a(0) =0a(1) =12a(2) =648a(3) =6084a(4) =30444a(5) =107376a(6) =302916a(7) =732024a(8) =1576728a(9) =3111012a(10) =5724852a(11) =9952620a(12) =16509336a(13) =26321160a(14) =40567872a(15) =60724104a(16) =88605480a(17) =126413772a(18) =176788476a(19) =242874756a(20) =328359624a(21) =437553360