Concatenate i >= 1 and j >= 1, then sort.

Terms

a(0) =11a(1) =12a(2) =13a(3) =14a(4) =15a(5) =16a(6) =17a(7) =18a(8) =19a(9) =21a(10) =22a(11) =23a(12) =24a(13) =25a(14) =26a(15) =27a(16) =28a(17) =29a(18) =31a(19) =32a(20) =33a(21) =34a(22) =35a(23) =36a(24) =37a(25) =38a(26) =39a(27) =41a(28) =42a(29) =43