AK: Pair by the river?

[sandycove]

So I know that with AK, the odds of one pair on the flop are 2.1:1 (32.4%).

And, having missed the flop, my odds of pairing one hole card are 3.2:1 (24%).

But what are my preflop odds of pairing one card by the river? And what is the calculation?

Also, what are the preflop odds of a pocket pair making trips by the river?