Triangle read by rows, generated from (..., 3, 2, 1).

Terms

a(0) =1a(1) =1a(2) =3a(3) =1a(4) =5a(5) =6a(6) =1a(7) =7a(8) =17a(9) =10a(10) =1a(11) =9a(12) =34a(13) =49a(14) =15a(15) =1a(16) =11a(17) =57a(18) =142a(19) =129a(20) =21a(21) =1a(22) =13a(23) =86a(24) =313a(25) =547a(26) =321a(27) =28a(28) =1a(29) =15