A031604 Numbers n such that continued fraction for sqrt(n) has odd period and central terms 16.

257, 1789, 3413, 5410, 5557, 5857, 8221, 11833, 12269, 14866, 15601, 19058, 19333, 19889, 24077, 24697, 25325, 30025, 31417, 35498, 35873, 36629, 37778, 41429, 42241, 43889, 45146, 55597, 56537, 57485, 58441, 60377, 62962, 63962, 64465, 67010, 70258