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Problem 878


Problem 878


XOR-Equation B

We use xy for the bitwise XOR of x and y.

Define the XOR-product of x and y, denoted by xy, similar to a long multiplication in base 2, except that the intermediate results are XORed instead of the usual integer addition.

For example, 73=9, or in base 2, 1112112=10012:
11111121111112111111211111291110012
We consider the equation:
(aa)(2ab)(bb)=k
For example, (a,b)=(3,6) is a solution to this equation for k=5.

Let G(N,m) be the number of solutions to those equations with km and 0abN.

You are given G(1000,100)=398.

Find G(1017,1 000 000).


异或等式(二)

xy表示xy按位异或的结果。

考虑xy2进制长乘法,但将中间结果的相加替换为按位异或,定义其结果为xy异或积,并记作xy

例如,73=9,或在2进制下,1112112=10012
11111121111112111111211111291110012
考虑等式:
(aa)(2ab)(bb)=k
例如,(a,b)=(3,6)是上式取k=5时的一个解。

若上式取遍所有km,考虑其所有满足0abN的解,记G(N,m)为所有这些解的数目。

已知G(1000,100)=398

G(1017,1 000 000)


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