Maximize XOR
C_K_Yang Walker liuguangxi a_forsteri Min_25 Philippe_57721 gerrob zilet sinan hervas lesnik7 R2D2 clytorock nielkh
Public  04/21/17  6xp  Programming  60.9% 
Let $ 2^k \le p \lt q \le 2^{k+1}1 $
We are looking for pairs (p,q) such as
$ \bullet \quad p \otimes q $ is maximal // $\otimes $ is the XOR operator.
$ \bullet \quad p, q$ are both either a prime or a square number
How many such pairs are there for k = 26 ?
Answer format: count,first p,first q
Example: 3,1307,1764 for k = 10
[My timing: 42 sec]
We are looking for pairs (p,q) such as
$ \bullet \quad p \otimes q $ is maximal // $\otimes $ is the XOR operator.
$ \bullet \quad p, q$ are both either a prime or a square number
How many such pairs are there for k = 26 ?
Answer format: count,first p,first q
Example: 3,1307,1764 for k = 10
[My timing: 42 sec]
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