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A308926
Sum of all the parts in the partitions of n into 7 parts.
7
0, 0, 0, 0, 0, 0, 0, 7, 8, 18, 30, 55, 84, 143, 210, 315, 448, 646, 882, 1235, 1640, 2205, 2882, 3772, 4824, 6200, 7800, 9828, 12208, 15138, 18540, 22723, 27520, 33297, 39950, 47845, 56844, 67488, 79534, 93600, 109520, 127920, 148638, 172473, 199144, 229590
OFFSET
0,8
FORMULA
a(n) = 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)} 1.
a(n) = n * A026813(n).
a(n) = A308927(n) + A308928(n) + A308929(n) + A308930(n) + A308931(n) + A308932(n) + A308933(n).
MATHEMATICA
Table[n*Sum[Sum[Sum[Sum[Sum[Sum[1, {i, j, Floor[(n - j - k - l - m - o)/2]}], {j, k, Floor[(n - k - l - m - o)/3]}], {k, l, Floor[(n - l - m - o)/4]}], {l, m, Floor[(n - m - o)/5]}], {m, o, Floor[(n - o)/6]}], {o, Floor[n/7]}], {n, 0, 50}]
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Jun 30 2019
STATUS
approved