a(n) = Sum_{k=0..floor(4*n/11)} binomial(k+3,4*n-11*k).

Terms

a(0) =1a(1) =0a(2) =0a(3) =4a(4) =0a(5) =0a(6) =10a(7) =0a(8) =0a(9) =20a(10) =0a(11) =1a(12) =35a(13) =0a(14) =8a(15) =56a(16) =0a(17) =36a(18) =84a(19) =0a(20) =120a(21) =120a(22) =1a(23) =330a(24) =165a(25) =12a(26) =792a(27) =220a(28) =78a(29) =1716