{ "data": { "question": { "questionId": "2882", "questionFrontendId": "2787", "boundTopicId": null, "title": "Ways to Express an Integer as Sum of Powers", "titleSlug": "ways-to-express-an-integer-as-sum-of-powers", "content": "

Given two positive integers n and x.

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Return the number of ways n can be expressed as the sum of the xth power of unique positive integers, in other words, the number of sets of unique integers [n1, n2, ..., nk] where n = n1x + n2x + ... + nkx.

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Since the result can be very large, return it modulo 109 + 7.

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For example, if n = 160 and x = 3, one way to express n is n = 23 + 33 + 53.

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Example 1:

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\nInput: n = 10, x = 2\nOutput: 1\nExplanation: We can express n as the following: n = 32 + 12 = 10.\nIt can be shown that it is the only way to express 10 as the sum of the 2nd power of unique integers.\n
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Example 2:

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\nInput: n = 4, x = 1\nOutput: 2\nExplanation: We can express n in the following ways:\n- n = 41 = 4.\n- n = 31 + 11 = 4.\n
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Constraints:

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