**a(1) = 1, a(n) = smallest positive number b not among a(1)..a(n-1) such that the last digit of b = the first digit of a(n-1).**

*1, 11, 21, 12, 31, 13, 41, 14, 51, 15, 61, 16, 71, 17, 81, 18, 91, 19, 101, 111, 121, 131*

*3 seqfan posts*

Index of A-numbers in seqfan: by ascending order by month by frequency by keyword

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