A158384 Positions of Pell numbers in the sequence of Markoff numbers (A002559).

1, 3, 5, 8, 13, 18, 25, 33, 41, 52, 64, 75, 90, 104, 119, 137, 157, 174, 193, 214, 236, 260, 289, 312, 340, 369, 396, 426, 458, 487, 523, 560, 596, 631, 671, 708, 751, 794, 835, 879, 924, 968, 1019, 1066, 1116, 1165, 1218, 1269, 1322, 1377, 1430, 1488, 1551