30101

Appears in sequences

• a(1) = 1; a(n+1) is the smallest number > a(n) which differs from it at every digit.at n=38A068860
• Łukasiewicz word for each rooted plane tree (interpretation e in Stanley's exercise 19) encoded by A014486 (or A063171), with the last leaf implicit, i.e., these words are given without the last trailing zero, except for the null tree which is encoded as 0.at n=29A071153
• Greater of number pair whose squares are reversals of each other, with no leading zeros allowed.at n=36A106324
• Semiprimes in A056108.at n=31A113527
• The sequence alternates even and odd integers but also even and odd digits; it is monotonically increasing and a(n) is always the smallest integer fitting the pattern.at n=19A137667
• Number of conjugacy classes for a non-abelian group of order p^3, where p is prime: a(n) = p^2 + p - 1 where p = prime(n).at n=39A319597
• T(n,k) is the k-th partition of n in graded reverse lexicographic ordering (A080577) encoded as concatenation of parts which are represented in (zeroless) bijective base-9 numeration (A052382) and separated by zeros; triangle T(n,k), n >= 0, 1 <= k <= A000041(n), read by rows.at n=15A332567
• Irregular triangle read by rows: row n lists the strings of the MIU formal system at the n-th level of the tree generated by recursively applying the system rules, starting from the MI string (see comments and example).at n=26A368946
• Irregular triangle read by rows: row n lists (in lexicographical order and with duplicates removed) the strings of the MIU formal system at the n-th level of the tree generated by recursively applying the system rules, starting from the MI string.at n=13A368953
• Irregular triangle read by rows: row n lists all of the distinct derivable strings in the MIU formal system that are n characters long.at n=14A369173