Number of distinct n X n patterns in the squiral tiling.

Terms

a(0) =1a(1) =2a(2) =14a(3) =70a(4) =126a(5) =270a(6) =438a(7) =630a(8) =790a(9) =958a(10) =1134a(11) =1542a(12) =1974a(13) =2430a(14) =2910a(15) =3414a(16) =3942a(17) =4494a(18) =5070a(19) =5670a(20) =6142a(21) =6622a(22) =7110a(23) =7606a(24) =8110a(25) =8622a(26) =9142a(27) =9670a(28) =10206a(29) =11406