Partial sums of A048695.

Terms

a(0) =1a(1) =9a(2) =26a(3) =68a(4) =169a(5) =413a(6) =1002a(7) =2424a(8) =5857a(9) =14145a(10) =34154a(11) =82460a(12) =199081a(13) =480629a(14) =1160346a(15) =2801328a(16) =6763009a(17) =16327353a(18) =39417722a(19) =95162804a(20) =229743337a(21) =554649485a(22) =1339042314a(23) =3232734120a(24) =7804510561a(25) =18841755249a(26) =45488021066a(27) =109817797388a(28) =265123615849