Shifts left when Euler transform applied 4 times.

Terms

a(0) =0a(1) =1a(2) =1a(3) =5a(4) =19a(5) =89a(6) =410a(7) =2052a(8) =10440a(9) =54874a(10) =293549a(11) =1597621a(12) =8807766a(13) =49107289a(14) =276358791a(15) =1567866228a(16) =8957204966a(17) =51486464912a(18) =297548288251