#4 in an infinite set of generalized Pascal's triangles with trigonometric properties.

Terms

a(0) =1a(1) =1a(2) =3a(3) =1a(4) =4a(5) =11a(6) =1a(7) =7a(8) =15a(9) =41a(10) =1a(11) =8a(12) =38a(13) =56a(14) =153a(15) =1a(16) =11a(17) =46a(18) =186a(19) =209a(20) =571a(21) =1a(22) =12a(23) =81a(24) =232a(25) =859a(26) =780a(27) =2131a(28) =1a(29) =15