a(0)=1, a(1)=1, a(n) = 11*a(n/2) for even n, and a(n) = 10*a((n-1)/2) + a((n+1)/2) for odd n >= 3.

Terms

a(0) =0a(1) =1a(2) =11a(3) =21a(4) =121a(5) =131a(6) =231a(7) =331a(8) =1331a(9) =1341a(10) =1441a(11) =1541a(12) =2541a(13) =2641a(14) =3641a(15) =4641a(16) =14641a(17) =14651a(18) =14751a(19) =14851a(20) =15851a(21) =15951a(22) =16951a(23) =17951a(24) =27951a(25) =28051a(26) =29051a(27) =30051a(28) =40051a(29) =41051