1235520

Appears in sequences

• Number of planar embedded labeled trees with n nodes: (2*n-3)!/(n-1)! for n >= 2, a(1) = 1.at n=7A006963
• Triangle read by rows: T(n, k) = [x^k] x*Pochhammer(n + x, n)/(n + x).at n=21A038455
• a(n) = (n+7)!/7!.at n=6A049388
• Generalized Stirling number triangle of first kind.at n=21A051379
• Product of 6 consecutive integers.at n=13A053625
• A unitary phi reciprocal amicable number: consider two different numbers r, s which satisfy the following equation for some integer k: uphi(r) = uphi(s) = (1/k) * r * s / (r-s); or equivalently, 1/uphi(r) = 1/uphi(s) = k * (1/s - 1/r); sequence gives s numbers.at n=29A080767
• 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=22A093447
• Least number (n+1)(n+2)(n+3)...(n+k) >= n^n.at n=6A108135
• 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=26A110768
• Volumes of Euler bricks.at n=0A118900
• Triangle read by rows: T(n,d) = (n!/d!)*(n+1)*binomial(2n-d+1,n+1)/(n-d+1) (0 <= d <= n).at n=21A123225
• Triangle read by rows: T(n,k) = k!*binomial(n+k-1,k) (n >= 0, 0 <= k <= n), rising factorial power, Pochhammer symbol.at n=42A124320
• Triangle of unsigned 4-Lah numbers.at n=21A143499
• A vector sequence with set row sum function: row(n)=(2*n)!/n! and linear build up and decline function: f(n,m)=Floor[(m/n)*row(n)].at n=29A152971
• A vector sequence with set row sum function: row(n)=(2*n)!/n! and linear build up and decline function: f(n,m)=Floor[(m/n)*row(n)].at n=34A152971
• Number of degree-n permutations of order exactly 7.at n=12A153760
• a(n) = prime(n)!/(n+1)!.at n=5A178614
• a(n) = n!/ceiling(n/2)!.at n=13A205825
• Positive numbers differing from next 3 greater squares by squares.at n=29A218487
• Number of pairs of orthogonal (-x,y) vectors of length 1*(x+y), where x/y is the n-th rational <= 1, ordered first by y and then x, e.g. 1/1, 1/2, 1/3, 2/3, 1/4, 3/4 ...at n=21A225986