a(n) = number of 3's between n-th 1 and (n+1)st 1 in A026600.

Terms

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