T(n,n-6), where T is the array in A055830.

Terms

a(0) =13a(1) =58a(2) =162a(3) =361a(4) =701a(5) =1239a(6) =2044a(7) =3198a(8) =4797a(9) =6952a(10) =9790a(11) =13455a(12) =18109a(13) =23933a(14) =31128a(15) =39916a(16) =50541a(17) =63270a(18) =78394a(19) =96229a(20) =117117a(21) =141427a(22) =169556a(23) =201930a(24) =239005a(25) =281268a(26) =329238a(27) =383467a(28) =444541a(29) =513081