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%I A309657 #7 Oct 07 2020 17:44:38
%S A309657 0,0,0,0,0,0,0,0,0,9,8,18,24,47,60,105,136,222,290,439,574,845,1088,
%T A309657 1527,1962,2681,3396,4526,5672,7396,9200,11768,14508,18326,22372,
%U A309657 27849,33774,41562,50002,60922,72764,87830,104254,124744,147156,174835,205016
%N A309657 Sum of the odd parts in the partitions of n into 9 parts.
%H A309657 Alois P. Heinz, <a href="/A309657/b309657.txt">Table of n, a(n) for n = 0..5000</a>
%H A309657 <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F A309657 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)} q * (q mod 2) + p * (p mod 2) + o * (o mod 2) + m * (m mod 2) + l * (l mod 2) + k * (k mod 2) + j * (j mod 2) + i * (i mod 2) + (n-i-j-k-l-m-o-p-q) * ((n-i-j-k-l-m-o-p-q) mod 2).
%t A309657 Table[Sum[Sum[Sum[Sum[Sum[Sum[Sum[Sum[i * Mod[i, 2] + j * Mod[j, 2] + k * Mod[k, 2] + l * Mod[l, 2] + m * Mod[m, 2] + o * Mod[o, 2] + p * Mod[p, 2] + q * Mod[q, 2] + (n - i - j - k - l - m - o - p - q) * Mod[n - i - j - k - l - m - o - p - q, 2], {i, j, Floor[(n - j - k - l - m - o - p - q)/2]}], {j, k, Floor[(n - k - l - m - o - p - q)/3]}], {k, l, Floor[(n - l - m - o - p - q)/4]}], {l, m, Floor[(n - m - o - p - q)/5]}], {m, o, Floor[(n - o - p - q)/6]}], {o, p, Floor[(n - p - q)/7]}], {p, q, Floor[(n - q)/8]}], {q, Floor[n/9]}], {n, 0, 50}]
%K A309657 nonn
%O A309657 0,10
%A A309657 _Wesley Ivan Hurt_, Aug 11 2019

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