A centered polygonal number consisting of a central dot with four dots around it, and then additional dots in the gaps between
adjacent dots. The general term is , and the first few such numbers are 1, 5, 13, 25,
41, ... (OEIS A001844). Centered square numbers
are the sum of two consecutive square numbers and
are congruent to 1 (mod 4). The generating function
giving the centered square numbers is
Conway, J. H. and Guy, R. K. The Book of Numbers. New York: Springer-Verlag, p. 41, 1996.Sloane,
N. J. A. Sequence A001844/M3826
in "The On-Line Encyclopedia of Integer Sequences."
, and the first few such numbers are 1, 5, 13, 25,
41, ... (OEIS A001844). Centered square numbers
are the sum of two consecutive square numbers and
are congruent to 1 (mod 4). The generating function
giving the centered square numbers is
