Number of terms in n-th derivative of a function composed with itself 7 times.

Terms

a(0) =1a(1) =1a(2) =7a(3) =28a(4) =105a(5) =322a(6) =952a(7) =2541a(8) =6539a(9) =15833a(10) =37148a(11) =83594a(12) =183289a(13) =389520a(14) =809820a(15) =1643375a(16) =3272797a(17) =6390745a(18) =12279337a(19) =23208483a(20) =43252360a(21) =79483096a(22) =144265338a(23) =258673983a(24) =458747540a(25) =804877837a(26) =1398356706a(27) =2406328974a(28) =4104352128a(29) =6940717598