The Numbers a2 + b2 − dc2
Nicolaus Copernicus University
Faculty of Mathematics and Computer Science
We say that a positive integer d is special if for every integer
there exist nonzero integers a, b, c such that
m = a2 + b2 − dc2.
this note we present examples and some properties of special numbers.
Moreover, we present an infinite sequence of special numbers.
Full version: pdf,
(Concerned with sequences
Received November 18 2014; revised versions received December 16 2014;
December 18 2014.
Published in Journal of Integer Sequences,
January 24 2015.
Journal of Integer Sequences home page