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%I #5 Aug 03 2019 08:44:07
%S 0,0,0,0,0,0,0,0,1,3,5,11,17,30,45,64,87,123,160,217,275,356,441,559,
%T 681,844,1016,1236,1470,1767,2075,2464,2871,3366,3892,4526,5188,5984,
%U 6820,7804,8843,10056,11327,12809,14363,16144,18023,20168,22414,24972
%N Number of prime parts in the partitions of n into 7 parts.
%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F 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)} (A010051(i) + A010051(j) + A010051(k) + A010051(l) + A010051(m) + A010051(o) + A010051(n-i-j-k-l-m-o)).
%t Table[Sum[Sum[Sum[Sum[Sum[Sum[(PrimePi[i] - PrimePi[i - 1]) + (PrimePi[j] - PrimePi[j - 1]) + (PrimePi[k] - PrimePi[k - 1]) + (PrimePi[l] - PrimePi[l - 1]) + (PrimePi[m] - PrimePi[m - 1]) + (PrimePi[o] - PrimePi[o - 1]) + (PrimePi[n - i - j - k - l - m - o] - PrimePi[n - i - j - k - l - m - o - 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}]
%Y Cf. A010051, A259197.
%K nonn
%O 0,10
%A _Wesley Ivan Hurt_, Aug 03 2019