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A340754
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Number of partitions of n into 4 parts such that the sum of the smallest two parts and the sum of the largest two parts are relatively prime.
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0
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0, 0, 0, 0, 0, 1, 0, 3, 1, 4, 2, 11, 1, 18, 7, 14, 11, 39, 10, 54, 14, 40, 31, 94, 26, 99, 53, 101, 49, 185, 34, 225, 102, 162, 123, 220, 96, 378, 174, 269, 160, 511, 117, 588, 229, 354, 314, 764, 235, 747, 318, 607, 395, 1089, 340, 882, 487, 849, 640, 1495, 406, 1650
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OFFSET
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0,8
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LINKS
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FORMULA
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a(n) = Sum_{k=1..floor(n/4)} Sum_{j=k..floor((n-k)/3)} Sum_{i=j..floor((n-j-k)/2)} floor(1/gcd(k+j,n-k-j)).
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MATHEMATICA
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Table[Sum[Sum[Sum[Floor[1/GCD[k + j, n - k - j]], {i, j, Floor[(n - j - k)/2]}], {j, k, Floor[(n - k)/3]}], {k, Floor[n/4]}], {n, 0, 80}]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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