First differences of A078482.

Terms

a(0) =1a(1) =1a(2) =4a(3) =14a(4) =50a(5) =184a(6) =694a(7) =2670a(8) =10440a(9) =41374a(10) =165830a(11) =671084a(12) =2738334a(13) =11254362a(14) =46547340a(15) =193592830a(16) =809165002a(17) =3397135168a(18) =14319385126a(19) =60576862358a(20) =257109077584