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A025466
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Number of partitions of n into 4 distinct nonnegative cubes.
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1
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0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0
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OFFSET
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0,541
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COMMENTS
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In other words, number of solutions to the equation n = w^3 + x^3 + y^3 + z^3 with w > x > y > z >= 0. - Antti Karttunen, Sep 21 2018
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LINKS
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EXAMPLE
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For n=540 we have two solutions: 540 = (0^3 + 1^3 + 3^3 + 8^3) = (2^3 + 4^3 + 5^3 + 7^3), thus a(540) = 2. This is the first point where a(n) > 1. - Antti Karttunen, Sep 21 2018
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PROG
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(PARI) A025466(n) = { my(s=0); for(w=0, n, if(ispower(w, 3), for(x=w+1, n-w, if(ispower(x, 3), for(y=x+1, n-(w+x), if(ispower(y, 3), for(z=y+1, n-(w+x+y), if((ispower(z, 3)&&(w+x+y+z)==n), s++)))))))); (s); }; \\ Antti Karttunen, Sep 21 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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