|
Search: id:A134941
|
|
| |
|
| 1, 121, 131, 141, 151, 161, 171, 181, 191, 1231, 1241, 1251, 1261, 1271, 1281, 1291, 1321, 1341, 1351, 1361, 1371, 1381, 1391, 1421, 1431, 1451, 1461, 1471, 1481, 1491, 1521, 1531, 1541, 1561, 1571, 1581, 1591, 1621, 1631, 1641, 1651, 1671
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
For n>1 the structure of digits represent a mountain. The first digit is 1. The last digit is 1. The first digits are in increasing order. The last digits are in decreasing order. The numbers only have one largest digit. This sequence is finite. The last member is 12345678987654321.
The total number of terms is 21846. - Hans Havermann (pxp(AT)rogers.com), Nov 25 2007
|
|
LINKS
|
J. Zucker, Table of n, a(n) for n = 1..21846 [Shows all terms]
|
|
EXAMPLE
|
The number of this sequence (A134941) is a mountain number:
. . . 9 . .
. . . . . .
. . . . . .
. . . . . .
. . . . . .
. . 4 . 4 .
. 3 . . . .
. . . . . .
1 . . . . 1
|
|
CROSSREFS
|
Cf. A134853, A135417.
|
|
KEYWORD
|
base,fini,nonn,new
|
|
AUTHOR
|
Omar E. Pol (info(AT)polprimos.com), Nov 22 2007, Dec 22 2007, May 18 2008, Dec 23 2008
|
|
|
Search completed in 0.002 seconds
|
