The total number of generalized mountain numbers is 173247.
Table of n, a(n) for n=1..18.
a(18) = 1 because there is exactly one generalized mountain number with 18 digits: 123456789876543210
Cf. A134853, A134941, A135417
Sequence in context: A157309 A215484 A177145 * A191564 A067479 A308803
Adjacent sequences: A178909 A178910 A178911 * A178913 A178914 A178915
Nathaniel Johnston, Dec 29 2010