INVERT transform of A000081 = [1, 1, 1, 2, 4, 9, 20, 48, 115, 286,...].

Terms

a(0) =1a(1) =2a(2) =4a(3) =9a(4) =21a(5) =51a(6) =126a(7) =318a(8) =812a(9) =2100a(10) =5482a(11) =14438a(12) =38303a(13) =102302a(14) =274824a(15) =742210a(16) =2013941a(17) =5488239a(18) =15014376a(19) =41221775a(20) =113542455a(21) =313681756a(22) =868994723a(23) =2413526848a(24) =6719132105a(25) =18746838609a(26) =52412080624a(27) =146812972155a(28) =411977724704