A050131 a(n) = n-th number k such that b(k)<b(k+1), where b=A050128.

1, 3, 4, 6, 9, 10, 12, 15, 17, 20, 22, 24, 27, 29, 32, 34, 37, 40, 42, 44, 46, 48, 51, 53, 56, 58, 61, 64, 66, 68, 71, 73, 76, 78, 81, 82, 84, 86, 88, 91, 93, 94, 96, 99, 101, 104, 106, 109, 112, 114, 116, 119, 121, 124, 126, 129, 130