121312

Appears in sequences

• Concatenation of n, n+1 and n.at n=11A261618
• a(n) = concatenation of n-th stage of the trajectory of 2 under the tribonacci morphism 1 -> {1, 2}, 2 -> {1, 3}, 3 -> {1}.at n=3A317196
• Bo Tan et al.'s string E_n, defined by A_n = A103269(n) = D_{n-1}E_n = A317197(n-1)E_n for n >= 2, with E_1 = 12.at n=3A317199
• Working over the alphabet {1,2,3}, start with a(1) = 1; then a(n+1) is made by inserting a letter into a(n) at the rightmost possible position which makes a squarefree word (and the smallest letter if multiple letters are possible at that place).at n=5A332603