Triangle T(n,k): write n in base 4, reverse order of digits.

Terms

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