A054169 Number of positive integers <= 2^n of form 4 x^2 + 5 y^2.

0, 0, 1, 2, 4, 7, 14, 25, 45, 84, 154, 290, 549, 1043, 1990, 3820, 7352, 14198, 27473, 53327, 103697, 201926, 393781, 769123, 1503776, 2943595, 5767727, 11310982, 22200249, 43604981, 85706123, 168562900, 331717805, 653148282, 1286697640

Offset

0,4

Links

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

Index entries for sequences related to populations of quadratic forms

Crossrefs

Cf. A020682.

Sequence in context: A360055 A347760 A218576 * A287185 A065491 A072810

Adjacent sequences: A054166 A054167 A054168 * A054170 A054171 A054172

Keyword

nonn

Author

David W. Wilson

Status

approved