A031424 Least term in period of continued fraction for sqrt(n), as n runs through the squarefree numbers > 1 (cf. A005117).

2, 1, 4, 2, 1, 1, 6, 3, 2, 1, 1, 1, 8, 4, 1, 2, 1, 1, 1, 1, 10, 5, 2, 1, 2, 1, 1, 1, 1, 1, 12, 6, 4, 3, 2, 2, 1, 1, 1, 1, 1, 1, 14, 7, 1, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 16, 8, 1, 4, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 18, 9, 6, 1, 1, 3, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 20, 10, 1, 5, 4, 1