Search Results for ""

The sum of the first n odd numbers is a square number, sum_(k=1)^n(2k-1)=n^2. A sort of converse also exists, namely the difference of the nth and (n-1)st square numbers is ...

In Book IX of The Elements, Euclid gave a method for constructing perfect numbers (Dickson 2005, p. 3), although this method applies only to even perfect numbers. In a 1638 ...

Any prime number other than 2 (which is the unique even prime). Humorously, 2 is therefore the "oddest" prime.

A circle-preserving transformation composed of an odd number of inversions.

Q is said to be tightly embedded if |Q intersection Q^g| is odd for all g in G-N_G(Q), where N_G(Q) is the normalizer of Q in G.

An odd Mathieu function se_r(z,q) with characteristic value a_r.

A partial order defined by (i-1, i), (i+1, i) for odd i.

A method for constructing magic squares of odd order.

An odd Walsh function with sequency k defined by Sal(n,k)=W(n,2k).

The graph complement of a graph hole. Graph antiholes are called even if they have an even number of vertices and odd if they have an odd number of vertices (Chvátal). No odd ...