A273812 - OEIS

A273812

Numbers that cannot be expressed as the sum of two nonzero squares and at most two powers of two.

1, 535903, 1072327, 1594807, 1750111, 2025783, 2822151, 3304447, 3566119, 3697543, 3855319, 3982759, 4874439, 5832831, 5930775, 6642975, 7115791, 7536567, 7591447, 7885135, 8058399, 8225991, 8307879, 8357079, 8900583, 9339775, 10071879, 10626655, 11274735, 11334943, 12046807, 12229255

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OFFSET

1,2

COMMENTS

If up to three powers of 2 are allowed (instead of two), then the smallest n > 1 which cannot be expressed is larger than 10^10. - Giovanni Resta, Jun 08 2016

Smallest n > 1 that can't be written as the sum of two squares and at most three powers of two is larger than 2^36. - David J. Platt, Aug 11 2016

LINKS

Table of n, a(n) for n=1..32.

R. C. Crocker, On the sum of two squares and two powers of k, Colloq. Math. 112(2008), 235-267.

Dave Platt, Tim Trudgian, On the sum of two squares and at most two powers of 2, arXiv:1610.01672 [math.NT], 2016.

CROSSREFS

Cf. A000404, A274050.

Sequence in context: A269322 A227497 A183650 * A210124 A237323 A251355

Adjacent sequences: A273809 A273810 A273811 * A273813 A273814 A273815

KEYWORD

nonn

AUTHOR

David J. Platt, May 31 2016

STATUS

approved