Number of (n+2) X 7 0..1 matrices with each 3 X 3 subblock idempotent.

Terms

a(0) =263a(1) =246a(2) =320a(3) =395a(4) =540a(5) =740a(6) =988a(7) =1351a(8) =1881a(9) =2623a(10) =3689a(11) =5243a(12) =7494a(13) =10763a(14) =15535a(15) =22504a(16) =32685a(17) =47578a(18) =69377a(19) =101291a(20) =148029a(21) =216494a(22) =316798a(23) =463762a(24) =679110a(25) =994678a(26) =1457123a(27) =2134826a(28) =3128004a(29) =4583531