OFFSET
1,2
COMMENTS
The number 1 is considered a power of two.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..10000
Dave Platt, Tim Trudgian, On the sum of two squares and at most two powers of 2, arXiv:1610.01672 [math.NT], 2016.
MATHEMATICA
nR[n_] := (SquaresR[2, n] + Plus @@ Pick[{-4, 4}, IntegerQ /@ Sqrt[{n, n/2}]])/8; bad[n_] := nR[n] == 0 && Block[{k = 1}, While[k < n && nR[n - k] == 0, k *= 2]; k >= n]; Select[Range@ 1000, bad]
CROSSREFS
KEYWORD
nonn
AUTHOR
Giovanni Resta, Jun 08 2016
STATUS
approved