A206582 The least number s having exactly n twos in the continued fraction of sqrt(s).

3, 2, 19, 45, 71, 153, 199, 589, 301, 989, 526, 1711, 739, 1633, 631, 3886, 1324, 4897, 2524, 7021, 2374, 4189, 2311, 10033, 3571, 3901, 2326, 8869, 4789, 10873, 6301, 10921, 6451, 11929, 6841, 12709, 7996, 13561, 7351, 19177, 9949, 16969, 12286, 22969, 11341

Offset

0,1

Links

Table of n, a(n) for n=0..44.

Mathematica

nn = 50; zeros = nn; t = Table[0, {nn}]; k = 2; While[zeros > 0, If[! IntegerQ[Sqrt[k]], cnt = Count[ContinuedFraction[Sqrt[k]][[2]], 2]; If[cnt <= nn && t[[cnt]] == 0, t[[cnt]] = k; zeros--]]; k++]; Join[{3}, t]

Crossrefs

Cf. A206578 (n ones), A206583 (n threes), A206584 (n fours), A206585 (n fives).

Sequence in context: A090587 A094554 A223881 * A154262 A367548 A154261

Adjacent sequences: A206579 A206580 A206581 * A206583 A206584 A206585

Keyword

nonn

Author

T. D. Noe, Mar 19 2012

Status

approved