a(n) = Sum_{k=0..floor(3*n/8)} binomial(k+1,3*n-8*k).

Terms

a(0) =1a(1) =0a(2) =0a(3) =2a(4) =0a(5) =0a(6) =3a(7) =0a(8) =1a(9) =4a(10) =0a(11) =5a(12) =5a(13) =0a(14) =15a(15) =6a(16) =1a(17) =35a(18) =7a(19) =8a(20) =70a(21) =8a(22) =36a(23) =126a(24) =10a(25) =120a(26) =210a(27) =21a(28) =330a(29) =330