A044431 Numbers n such that string 9,9 occurs in the base 10 representation of n but not of n-1.

99, 199, 299, 399, 499, 599, 699, 799, 899, 990, 1099, 1199, 1299, 1399, 1499, 1599, 1699, 1799, 1899, 1990, 2099, 2199, 2299, 2399, 2499, 2599, 2699, 2799, 2899, 2990, 3099, 3199, 3299, 3399, 3499, 3599, 3699, 3799, 3899