Triangle read by rows: k-th "a-number" of star graph K_{1,n-1}.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =2a(6) =1a(7) =3a(8) =2a(9) =1a(10) =4a(11) =8a(12) =1a(13) =5a(14) =20a(15) =16a(16) =1a(17) =6a(18) =40a(19) =96a(20) =1a(21) =7a(22) =70a(23) =336a(24) =272a(25) =1a(26) =8a(27) =112a(28) =896a(29) =2176