A044874 Numbers having, in base 3, (sum of even run lengths)=(sum of odd run lengths).
28, 29, 31, 35, 37, 38, 42, 43, 45, 49, 51, 52, 55, 56, 58, 62, 63, 66, 68, 71, 73, 74, 75, 77, 2197, 2198, 2200, 2202, 2203, 2206, 2207, 2208, 2210, 2213, 2223, 2227, 2231, 2259, 2263, 2267, 2271, 2273, 2274, 2275, 2277, 2280
Offset: 1