657720

Appears in sequences

• Products of 4 consecutive integers: a(n) = n*(n-1)*(n-2)*(n-3).at n=30A052762
• a(n) = n*(n-1)*(n-2)*(n-3) for n>=5.at n=30A052768
• a(n) = (6*n)!/(5*n+1)!.at n=5A052795
• Triangle a(n,k) read by rows n which contain columns k=1,2,..,n, where each entry is the product of numbers (k-1)*n-T(k-2)+1 through k*n-T(k-1).at n=32A093447
• The r-th term of the n-th row of the following triangle contains product of r successive numbers in decreasing order beginning from T(n)-T(r-1) where T(n) is the n-th triangular number. 1 3 2 6 20 6 10 72 210 24 15 182 1320 3024 120 ... Sequence contains the triangle by rows.at n=31A110768
• The Hyper-Wiener index of a link of n fullerenes C_{20} (see the Ghorbani and Hosseinzadeh reference).at n=6A216115
• Average of amicable pairs (x,y), ordered by the smaller value x given in A002025.at n=32A275315
• Average of amicable pairs (x,y), ordered by the sum x+y given in A259953.at n=33A275316
• Denominators of r(n) := Sum_{k=0..n-1} 1/Product_{j=0..4} (k + j + 1), for n >= 0, with r(0) = 0.at n=26A300299
• Irregular triangle read by rows: T(n,k) is the number of arrangements of n labeled children with exactly k nontrivial rounds; n >= 3, 1 <= k <= floor(n/3).at n=13A349426
• Numbers of the form (p+1)*(p+3) where (p,p+2) is a twin prime pair (cf. A001359).at n=30A362941