A054166 Number of positive integers <= 2^n of form 3 x^2 + 9 y^2.

0, 0, 1, 1, 3, 5, 10, 17, 32, 56, 106, 195, 365, 691, 1308, 2495, 4773, 9174, 17671, 34144, 66131, 128330, 249482, 485761, 947206, 1849299, 3614605, 7072464, 13851148, 27150649, 53262111, 104562496, 205412762, 403786919, 794202162

Offset

0,5

Links

Table of n, a(n) for n=0..34.

Index entries for sequences related to populations of quadratic forms

Crossrefs

Sequence in context: A018072 A090170 A301751 * A265317 A054157 A215982

Adjacent sequences: A054163 A054164 A054165 * A054167 A054168 A054169

Keyword

nonn

Author

David W. Wilson

Status

approved