Numbers to the left of the central numbers of the (2,1)-Pascal triangle A029653.

Terms

a(0) =2a(1) =2a(2) =2a(3) =5a(4) =2a(5) =7a(6) =2a(7) =9a(8) =16a(9) =2a(10) =11a(11) =25a(12) =2a(13) =13a(14) =36a(15) =55a(16) =2a(17) =15a(18) =49a(19) =91a(20) =2a(21) =17a(22) =64a(23) =140a(24) =196a(25) =2a(26) =19a(27) =81a(28) =204a(29) =336