Number of (n+1) X 7 0..2 arrays with all 2 X 2 subblock sums the same.

Terms

a(0) =5175a(1) =6417a(2) =8415a(3) =12525a(4) =19935a(5) =35565a(6) =66591a(7) =134853a(8) =282735a(9) =628557a(10) =1444815a(11) =3494805a(12) =8731935a(13) =22771005a(14) =60933951a(15) =168205893a(16) =472111695a(17) =1351666797a(18) =3905565615a(19) =11418586485a(20) =33538635135a(21) =99183404445a(22) =293959431711