Binomial transform of A001156.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =17a(5) =38a(6) =86a(7) =192a(8) =420a(9) =905a(10) =1939a(11) =4163a(12) =8987a(13) =19494a(14) =42368a(15) =91990a(16) =199127a(17) =429345a(18) =921982a(19) =1972553a(20) =4206909a(21) =8949412a(22) =19001874a(23) =40293048a(24) =85373962a(25) =180826115a(26) =382957231a(27) =811027414a(28) =1717497958a(29) =3636335170