Erroneous version of A007894.

Terms

a(0) =6a(1) =15a(2) =17a(3) =40a(4) =49a(5) =89a(6) =116a(7) =199a(8) =271a(9) =437a(10) =580a(11) =924a(12) =1205a(13) =1812a(14) =2385a(15) =3465a(16) =4478a(17) =6332a(18) =8149a(19) =11190a(20) =14246