The number of indecomposable Schur rings over a cyclic 2-group.
The number of inequivalent optimal covering codes.
The number of inversions in permutations: A saddle point approach.
The number of isomorphism classes of spanning trees of a graph
The number of knight's tours equals 33, 439, 123, 484, 294—counting with binary decision diagrams.
The number of labeled 2-connected planar graphs.
The Number of Labeled Dissections of a k-Ball.
The number of labelled -arch graphs.
The Number of Non-Isomorphic Hamiltonian Circuits in an -Dimensional Cube
The number of [old-time] basketball games with final score : where the home team was never losing but also never ahead by more than points.
The number of orthogonal Latin squares
The number of prime factors of binomial coefficients
The number of ribbon Schur functions.
The number of spanning trees and chains of graphs.
The number of spanning trees of double graphs
The number of ternary words avoiding abelian cubes grows exponentially.
The number of triangles formed by intersecting diagonals of a regular polygon.
The number of triangles in a tringulation of a set of points in the plane.
The Number-System of Algebra [Book]
The number-theoretic content of the Jacobi triple product identity.