Crystal ball sequence for D_6 lattice.

Terms

a(0) =1a(1) =61a(2) =853a(3) =5577a(4) =23673a(5) =76389a(6) =204205a(7) =476113a(8) =1000753a(9) =1939405a(10) =3520837a(11) =6058009a(12) =9966633a(13) =15785589a(14) =24199197a(15) =36061345a(16) =52421473a(17) =74552413a(18) =103980085a(19) =142515049a(20) =192285913a(21) =255774597a(22) =335853453