This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A333555 #14 Mar 28 2020 17:06:20 %S A333555 1,2,4,8,5,16,32,17,64,18,37,128,19,39,72,38,30,256,20,34,66,234,512, %T A333555 22,41,103,174,258,60,236,1024,23,71,50,267,24,169,526,127,285,2048, %U A333555 28,47,187,69,378,523,272,1063,367,591,193,475,4096,31,65,176,277 %N A333555 Lexicographically earliest infinite sequence of positive terms such that for any two distinct nonempty intervals, say [t, u] and [v, w], a(t) XOR ... XOR a(u) <> a(v) XOR ... XOR a(w) (where XOR denotes the bitwise XOR operator). %C A333555 By necessity, all terms are distincts. %C A333555 Also, for any m and n such that m <= n, a(m) XOR ... XOR a(n) > 0. %C A333555 This sequence has similarities with A101274; here we combine consecutive terms with the XOR operator, there with the classic addition. %H A333555 Rémy Sigrist, <a href="/A333555/b333555.txt">Table of n, a(n) for n = 1..8747</a> %H A333555 Rémy Sigrist, <a href="/A333555/a333555.txt">C program for A333555</a> %e A333555 The values of a(u) XOR ... XOR a(v) for u <= v <= 10 are: %e A333555 u\v| 1 2 3 4 5 6 7 8 9 10 %e A333555 ---+--------------------------------------- %e A333555 1| 1 3 7 15 10 26 58 43 107 121 --> A333556(v) %e A333555 2| . 2 6 14 11 27 59 42 106 120 %e A333555 3| . . 4 12 9 25 57 40 104 122 %e A333555 4| . . . 8 13 29 61 44 108 126 %e A333555 5| . . . . 5 21 53 36 100 118 %e A333555 6| . . . . . 16 48 33 97 115 %e A333555 7| . . . . . . 32 49 113 99 %e A333555 8| . . . . . . . 17 81 67 %e A333555 9| . . . . . . . . 64 82 %e A333555 10| . . . . . . . . . 18 %o A333555 (C) See Links section. %Y A333555 Cf. A101274, A333556. %K A333555 nonn,look,base %O A333555 1,2 %A A333555 _Rémy Sigrist_, Mar 26 2020