We assume page A has pages T1...Tn which point to it (i.e., are citations).

The parameter d is a damping factor which can be set between 0 and 1.
We usually set d to 0.85. There are more details about d in the next section.
Also C(A) is defined as the number of links going out of page A.

The PageRank of a page A is given as follows:

PR(A) = (1-d) + d (PR(T1)/C(T1) + ... + PR(Tn)/C(Tn))

Note that the PageRanks form a probability distribution over web pages,
so the sum of all web pages' PageRanks will be one.

PageRank or PR(A) can be calculated using a simple iterative algorithm,
and corresponds to the principal eigenvector of the normalized link matrix of the web.