A044810 Numbers n such that string 9,7 occurs in the base 10 representation of n but not of n+1.

97, 197, 297, 397, 497, 597, 697, 797, 897, 979, 997, 1097, 1197, 1297, 1397, 1497, 1597, 1697, 1797, 1897, 1979, 1997, 2097, 2197, 2297, 2397, 2497, 2597, 2697, 2797, 2897, 2979, 2997, 3097, 3197, 3297, 3397, 3497, 3597