Number of unimodal functions [1..n]->[0..2].

Terms

a(0) =1a(1) =3a(2) =9a(3) =22a(4) =46a(5) =86a(6) =148a(7) =239a(8) =367a(9) =541a(10) =771a(11) =1068a(12) =1444a(13) =1912a(14) =2486a(15) =3181a(16) =4013a(17) =4999a(18) =6157a(19) =7506a(20) =9066a(21) =10858a(22) =12904a(23) =15227a(24) =17851a(25) =20801a(26) =24103a(27) =27784a(28) =31872a(29) =36396