Number of regular tetrahedra in an n-node-per-edge tetrahedral grid.

Terms

a(0) =0a(1) =0a(2) =1a(3) =5a(4) =16a(5) =39a(6) =80a(7) =155a(8) =281a(9) =476a(10) =760a(11) =1154a(12) =1686a(13) =2394a(14) =3331a(15) =4551a(16) =6110a(17) =8065a(18) =10486a(19) =13461a(20) =17079a(21) =21430a(22) =26606a(23) =32726a(24) =39928a(25) =48360a(26) =58183a(27) =69573a(28) =82708a(29) =97767