174096

Appears in sequences

• a(n) = (4*n^2 + 2*n - 3)*(2*n - 1)*n/3.at n=16A058581
• a(n) = binomial(n+2,2) * binomial(n+7,2).at n=25A104676
• Irregular triangle read by rows: T(n,k) (n>=2, 1<=k<=n) gives number of arrangements of the elements from the multiset M(n, 3) into exactly k disjoint cycles.at n=43A245183
• Average of amicable pairs (x,y), ordered by the smaller value x given in A002025.at n=18A275315
• Average of amicable pairs (x,y), ordered by the sum x+y given in A259953.at n=18A275316
• a(n) = 4*3*2*1 + 8*7*6*5 + 12*11*10*9 + 16*15*14*13 + ... + (up to the n-th term).at n=21A319868
• Number of n-vertex, 2-edge multigraphs that are not nesting. Number of n-vertex, 2-edge multigraphs that are not crossing.at n=32A326278