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A162501
Lexicographically earliest permutation of the natural numbers such that in decimal representation the initial digit for each term is equal to the last nonzero digit of its predecessor; a(1)=1.
9
1, 10, 11, 12, 2, 20, 21, 13, 3, 30, 31, 14, 4, 40, 41, 15, 5, 50, 51, 16, 6, 60, 61, 17, 7, 70, 71, 18, 8, 80, 81, 19, 9, 90, 91, 100, 101, 102, 22, 23, 32, 24, 42, 25, 52, 26, 62, 27, 72, 28, 82, 29, 92, 200, 201, 103, 33, 34, 43, 35, 53, 36, 63, 37, 73, 38, 83, 39, 93, 300, 301
OFFSET
1,2
COMMENTS
A000030(a(n+1)) = A065881(a(n));
inverse of A162502: a(A162502(n)) = A162502(a(n)) = n;
a(a(n)) = A162503(n).
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Reinhard Zumkeller, Jul 05 2009
STATUS
approved