Number of arrays of the median of three adjacent elements of some length 7 0..n array.

Terms

a(0) =28a(1) =185a(2) =696a(3) =1943a(4) =4504a(5) =9191a(6) =17088a(7) =29589a(8) =48436a(9) =75757a(10) =114104a(11) =166491a(12) =236432a(13) =327979a(14) =445760a(15) =595017a(16) =781644a(17) =1012225a(18) =1294072a(19) =1635263a(20) =2044680a(21) =2532047a(22) =3107968a(23) =3783965a(24) =4572516a(25) =5487093a(26) =6542200a(27) =7753411a(28) =9137408a(29) =10712019