112122

Appears in sequences

• List of Lyndon words on {1,2} sorted first by length and then lexicographically.at n=18A102659
• Ternary emirpimes.at n=39A119684
• Sorted list of strings that can be obtained by starting with 12 and repeatedly doubling any substring in place.at n=20A130838
• Denominators of an Egyptian fraction for 1/Sqrt[24] = 0.20412414523...at n=2A144999
• 6-digit numbers k such that: (a) the digits of k are from the set {1, 2, 3, 4, 5}, and (b) any digit that appears in k appears at least twice.at n=19A171725
• Upper Beatty array of sqrt(3).at n=46A182786
• Smallest (i.e., rightmost) Lyndon word in the Lyndon factorization of the binary representation of n (written using 1's and 2's rather than 0's and 1's, since numbers > 0 in the OEIS cannot begin with 0).at n=75A211096
• Largest (i.e., leftmost) Lyndon word in Lyndon factorization of binary vectors of lengths 1, 2, 3, ... (written using 1's and 2's rather than 0's and 1's, since numbers > 0 in the OEIS cannot begin with 0).at n=73A211099
• List of subwords (or factors) of the Thue-Morse "1,2"-word A001285.at n=34A214215
• List of words over {1,2} with equal numbers of 1's and 2's.at n=9A214218
• List of minimal palindromic words over {1,2} that begin with 1, and have lengths 1, 2, 3, ....at n=10A225189
• Minimal representation (considered minimal in any canonical base b >= 3) of n in a binary system using two distinct digits "1" and "2", not allowing zeros, where a digit d in position p (p = 1,2,3,...,n) represents the value d^p.at n=24A235860
• List of words of length n over an alphabet of size 9 that are in standard order and which have the property that every letter that appears in the word is repeated.at n=24A273978
• Consider the Post tag system described in A284116 (but adapted to the alphabet {1,2}) ; sequence lists the words that terminate in the empty word.at n=39A289675
• Take n-th string over {1,2} in lexicographic order and apply the Watanabe tag system {00, 1011} described in A291067 (but adapted to the alphabet {1,2}) just once.at n=46A291072
• a(1) = 1; a(2) = 2; for n > 2, a(n) is the least number > a(n-1) whose decimal representation is uniquely the concatenation of the decimal representations of two distinct earlier terms.at n=33A336528
• List of subwords (or factors) of the Kolakoski sequence (A000002).at n=37A376677