Problem 178
Step Numbers
Consider the number 45656.
It can be seen that each pair of consecutive digits of 45656 has a difference of one.
A number for which every pair of consecutive digits has a difference of one is called a step number.
A pandigital number contains every decimal digit from 0 to 9 at least once.
How many pandigital step numbers less than 1040 are there?
台阶数
考虑整数45656。
可以看出45656的每一对相邻数字之间都差1。
这种任意一对相邻数字之间都差1的数称为台阶数。
一个全数字数包含有0到9这10个数字至少各一次。
在小于1040的数中，有多少个全数字台阶数？