Table read by rows: 1 if x = y, 0 otherwise, where (x,y) = (0,0),(0,1),(1,0),(0,2),(1,1),(2,0),...

Terms

a(0) =1a(1) =0a(2) =0a(3) =0a(4) =1a(5) =0a(6) =0a(7) =0a(8) =0a(9) =0a(10) =0a(11) =0a(12) =1a(13) =0a(14) =0a(15) =0a(16) =0a(17) =0a(18) =0a(19) =0a(20) =0a(21) =0a(22) =0a(23) =0a(24) =1a(25) =0a(26) =0a(27) =0a(28) =0a(29) =0