a(n) = Sum_{k=0..n} A026626(n, k).

Terms

a(0) =1a(1) =2a(2) =5a(3) =10a(4) =22a(5) =44a(6) =90a(7) =180a(8) =362a(9) =724a(10) =1450a(11) =2900a(12) =5802a(13) =11604a(14) =23210a(15) =46420a(16) =92842a(17) =185684a(18) =371370a(19) =742740a(20) =1485482a(21) =2970964a(22) =5941930a(23) =11883860a(24) =23767722a(25) =47535444a(26) =95070890a(27) =190141780a(28) =380283562a(29) =760567124