Use bit-shift in example in README instead.

README.md

@@ -29,7 +29,7 @@ To start with we computed by brute force the first thirteen non-negative integer
 
 Similarly, we assign the integer values 0, 1, 8 and 57 for spade, heart, diamond and club respectively. Any sum of exactly seven values taken from {0, 1, 8, 57} is unique among all such sums. We add up the suits of a 7-card hand to produce a "flush check" key and use this to look up the flush suit value if any. The largest flush key we see is 7999, corresponding to any of the four 7-card straight flushes with ace high, and the largest suit key is 399.
 
-The extraordinarily lucky aspect of this is that the maximum non-flush key we have, 7825759, is a 23-bit integer (note 2^23 = 8388608) and the largest suit key we find, 57*7 = 399, is a 9-bit integer (note 2^9 = 512). If we bit-shift each card's flush check and add to this its non-flush face value to make a card key in advance, when we aggregate the resulting card keys over a given 7-card hand we generate a 23+9 = 32-bit integer key for the whole hand. This integer key can only just be accommodated by a standard 32-bit `int` type and yet still carries enough information to decide if we're looking at a flush and if not to then look up the rank of the hand.
+The extraordinarily lucky aspect of this is that the maximum non-flush key we have, 7825759, is a 23-bit integer (note 1<<23 = 8388608) and the largest suit key we find, 57*7 = 399, is a 9-bit integer (note 1<<9 = 512). If we bit-shift each card's flush check and add to this its non-flush face value to make a card key in advance, when we aggregate the resulting card keys over a given 7-card hand we generate a 23+9 = 32-bit integer key for the whole hand. This integer key can only just be accommodated by a standard 32-bit `int` type and yet still carries enough information to decide if we're looking at a flush and if not to then look up the rank of the hand.
 
 ## How has the project evolved?