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A252490 Numbers whose set of digits is simply connected, with 9 and 0 considered as neighbors. 2
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 21, 22, 23, 32, 33, 34, 43, 44, 45, 54, 55, 56, 65, 66, 67, 76, 77, 78, 87, 88, 89, 90, 98, 99, 100, 101, 102, 109, 110, 111, 112, 120, 121, 122, 123, 132, 190, 201, 210, 211, 212, 213, 221, 222, 223, 231, 232, 233, 234, 243, 312, 321, 322, 323, 324, 332, 333, 334, 342, 343, 344, 345, 354, 423, 432 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The set of digits must consist in a single run without "holes", but for a cyclic topology where 9 and 0 are seen as neighbors.

A superset of A134336. Namely, numbers in A134336 or such that the complement of their digits in {0,...,9} satisfies the criterion of A134336.

LINKS

Danny Rorabaugh, Table of n, a(n) for n = 1..10000

PROG

(PARI) is(n)=vecmax(if((d=Set(digits(n)))[1], d, d=setminus(vector(9, i, i), d)))-vecmin(d)==#d-1

CROSSREFS

Cf. A032981, A050278, A033075 (a subsequence), A010785, A108965, A134336 (a subsequence).

Sequence in context: A261370 A257737 A130577 * A178403 A134336 A131207

Adjacent sequences:  A252487 A252488 A252489 * A252491 A252492 A252493

KEYWORD

nonn,base,easy

AUTHOR

M. F. Hasler, Dec 24 2014

STATUS

approved

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Last modified March 23 09:20 EDT 2019. Contains 321424 sequences. (Running on oeis4.)