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%I #9 Dec 03 2023 17:32:06
%S 0,0,0,0,0,0,0,0,0,1,1,3,5,10,15,27,39,63,91,135,188,272,368,510,682,
%T 918,1201,1586,2039,2639,3354,4264,5346,6716,8319,10312,12657,15516,
%U 18858,22908,27599,33226,39740,47449,56338,66809,78792,92799,108810,127365
%N Sum of the second largest parts of the partitions of n into 9 parts.
%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F a(n) = Sum_{q=1..floor(n/9)} Sum_{p=q..floor((n-q)/8)} Sum_{o=p..floor((n-p-q)/7)} Sum_{m=o..floor((n-o-p-q)/6)} Sum_{l=m..floor((n-m-o-p-q)/5)} Sum_{k=l..floor((n-l-m-o-p-q)/4)} Sum_{j=k..floor((n-k-l-m-o-p-q)/3)} Sum_{i=j..floor((n-j-k-l-m-o-p-q)/2)} i.
%F a(n) = A326464(n) - A326465(n) - A326466(n) - A326467(n) - A326468(n) - A326469(n) - A326470(n) - A326471(n) - A326473(n).
%t Table[Total[IntegerPartitions[n,{9}][[;;,2]]],{n,0,50}] (* _Harvey P. Dale_, Dec 03 2023 *)
%Y Cf. A026815, A326464, A326465, A326466, A326467, A326468, A326469, A326470, A326471, A326473.
%K nonn
%O 0,12
%A _Wesley Ivan Hurt_, Jul 10 2019
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