1,1

Integers n that cannot be expressed as the product of two numbers of the form a + b*sqrt(-11), where a > 0 and b >= 0 (excluding 1 and n).

Table of n, a(n) for n=1..58.

a(n) ~ 6/5 * n log n.

(MAGMA) Sort([11] cat [p: p in PrimesUpTo(317) | NormEquation(11, p) eq false]);

Cf. A033209.

Sequence in context: A329191 A154363 A049555 * A052042 A245576 A086472

Adjacent sequences: A281292 A281293 A281294 * A281296 A281297 A281298

nonn

Arkadiusz Wesolowski, Jan 19 2017

approved