Number of arrays of maxima of three adjacent elements of some length 8 0..n array.

Terms

a(0) =27a(1) =183a(2) =736a(3) =2227a(4) =5615a(5) =12453a(6) =25096a(7) =46941a(8) =82699a(9) =138699a(10) =223224a(11) =346879a(12) =522991a(13) =768041a(14) =1102128a(15) =1549465a(16) =2138907a(17) =2904511a(18) =3886128a(19) =5130027a(20) =6689551a(21) =8625805a(22) =11008376a(23) =13916085a(24) =17437771a(25) =21673107a(26) =26733448a(27) =32742711a(28) =39838287