

A363765


Lexicographically earliest sequence of numbers in a hexagonal spiral such that their neighbors have no common digit.


2



0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 44, 11, 20, 13, 22, 14, 23, 15, 24, 16, 25, 17, 26, 33, 27, 30, 28, 34, 55, 29, 40, 35, 60, 57, 46, 37, 18, 39, 47, 19, 36, 45, 70, 12, 48, 51, 49, 31, 50, 21, 38, 41, 53, 61, 42, 58, 32, 80, 52, 64, 59, 62, 81, 56, 43, 72
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OFFSET

1,3


COMMENTS

This sequence ends with 672 terms.


LINKS



EXAMPLE

a(26) = 27 because the neighbors of the 26th hexagon are 10, 30, 33, 44, 48, 51 who have no common digit with 27.
a(673) can't be calculated because its neighbors would be 216, 397 and 548 and they are using all digits.


CROSSREFS



KEYWORD

base,nonn,fini,full


AUTHOR



STATUS

approved



