

A160343


The sequence contains numbers n such that the two closest numbers above and below n, which are in A010784 and which have no common digit with n, have the same distance to n.


0



1, 2, 3, 4, 5, 6, 7, 8, 9, 89, 394, 605, 894, 3944, 6055, 8944, 15111, 84888, 89444, 894444
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,2


COMMENTS

For each integer n define the smallest upper neighbor n+d in the range d>0, such that n+d contains each digit at most once (see A010784) and such that n+d has none of the digits of n. Define also the largest lower neighbor nb in the range b>0, such that nb contains each digit at most once and such that nb has none of the digits of n.
The sequence contains those n where d=b, that is, where these two neighbors have the same distance to n.
From Donovan Johnson, Sep 29 2009: (Start)
15111 has neighbors 9876 and 20346, distance 5235.
84888 has neighbors 79653 and 90123, distance 5235.
89444 has neighbors 76532 and 102356, distance 12912.
894444 has neighbors 765321 and 1023567, distance 129123.
Sequence is complete.
(End)


LINKS

Table of n, a(n) for n=1..20.
Rodolfo Kurchan and Claudio Meller, Snark email list, May 10, 2009


EXAMPLE

6 has neighbors 5 and 7, common distance 1.
89 has neighbors 76 and 102, common distance 13.
394 has neighbors 287 and 501, distance 107.
605 has neighbors 498 and 712, distance 107.
894 has neighbors 765 and 1023, distance 129.
3944 has neighbors 2876 and 5012, distance 1068.
6055 has neighbors 4987 and 7123, distance 1068.
8944 has neighbors 7653 and 10235, distance 1291.
94 is not in the sequence because 87 and 102 have distances 7 and 8.


CROSSREFS

Sequence in context: A098766 A032799 A208130 * A239085 A024664 A078188
Adjacent sequences: A160340 A160341 A160342 * A160344 A160345 A160346


KEYWORD

base,fini,nonn,full


AUTHOR

Rodolfo Kurchan, May 10 2009, May 11 2009, May 16 2009


EXTENSIONS

Edited by R. J. Mathar, May 20 2009
a(17)a(20) from Donovan Johnson, Sep 29 2009


STATUS

approved



