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A308931
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Sum of the third largest parts in the partitions of n into 7 parts.
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7
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0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 4, 7, 11, 19, 28, 42, 61, 88, 121, 171, 228, 307, 405, 531, 682, 880, 1111, 1403, 1750, 2174, 2670, 3281, 3983, 4827, 5807, 6965, 8291, 9861, 11641, 13718, 16080, 18804, 21881, 25423, 29392, 33921, 39001, 44753, 51163, 58411
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OFFSET
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0,10
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LINKS
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FORMULA
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a(n) = Sum_{o=1..floor(n/7)} Sum_{m=o..floor((n-o)/6)} Sum_{l=m..floor((n-m-o)/5)} Sum_{k=l..floor((n-l-m-o)/4)} Sum_{j=k..floor((n-k-l-m-o)/3} Sum_{i=j..floor((n-j-k-l-m-o)/2)} j.
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MATHEMATICA
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Table[Total[IntegerPartitions[n, {7}][[All, 3]]], {n, 0, 50}] (* Harvey P. Dale, Aug 15 2020 *)
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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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