

A183086


Generalized canyon numbers.


1



101, 102, 103, 104, 105, 106, 107, 108, 109, 201, 202, 203, 204, 205, 206, 207, 208, 209, 212, 213, 214, 215, 216, 217, 218, 219, 301, 302, 303, 304, 305, 306, 307, 308, 309, 312, 313, 314, 315, 316, 317, 318, 319, 323, 324, 325, 326, 327, 328, 329, 401, 402, 403, 404, 405, 406, 407, 408, 409, 412
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OFFSET

1,1


COMMENTS

Supersequence of A134970. The structure of digits represent a canyon (a deep valley between cliffs). The first digits are in decreasing order. The last digits are in increasing order. There is only one smaller digit which represents the bottom of the canyon. But the restriction that both cliffs are at same level (first digit equal to the final digit) is dropped here.
This sequence is finite. The largest term is 9876543210123456789.
Question: How many terms are there in this sequence?


LINKS

Table of n, a(n) for n=1..60.


EXAMPLE

Illustration of 751378 as a generalized canyon number:
. . . . . .
. . . . . 8
7 . . . 7 .
. . . . . .
. 5 . . . .
. . . . . .
. . . 3 . .
. . . . . .
. . 1 . . .
. . . . . .


CROSSREFS

Cf. A134853, A134970, A183087.
Sequence in context: A043639 A152054 A296883 * A134808 A274612 A261448
Adjacent sequences: A183083 A183084 A183085 * A183087 A183088 A183089


KEYWORD

nonn,base,fini


AUTHOR

Omar E. Pol, Jan 19 2011


STATUS

approved



