10-substrings (noch nicht übersetzt)

A 10-substring of a number is a substring of its digits that sum to 10. For example, the 10-substrings of the number 3523014 are:

• 3523014
• 3523014
• 3523014
• 3523014

A number is called 10-substring-friendly if every one of its digits belongs to a 10-substring. For example, 3523014 is 10-substring-friendly, but 28546 is not.

Let T(n) be the number of 10-substring-friendly numbers from 1 to 10ⁿ (inclusive).
For example T(2) = 9 and T(5) = 3492.

Find T(10¹⁸) mod 1 000 000 007.