1632960

Appears in sequences

• Triangle whose (i,j)-th entry is binomial(i,j)*5^(i-j)*6^j.at n=34A038248
• Triangle whose (i,j)-th entry is binomial(i,j)*6^(i-j)*5^j.at n=29A038259
• a(n) = (3*n+9)!!!/9!!!, related to A032031 ((3*n)!!! triple factorials).at n=5A051609
• Expansion of e.g.f. (1-x)/(1-2*x-2*x^2+2*x^3).at n=7A052575
• Consider the solutions to k = a+b = x*y and a*b = k*(x+y) where k, a, b, x, and y are all positive integers, ordered by increasing k and, in case of ties, by increasing x. Sequence gives values of a*b.at n=26A057421
• For the numbers k that can be expressed as k = w + x = y*z with w*x = y^3 + z^3 where w, x, y, and z are all positive integers, this sequence gives the corresponding values of w*x.at n=23A057443
• Least number whose number of divisors is n-th term from A014613 (numbers of form p*q*r*s, products of exactly 4 primes, counted with multiplicity).at n=23A061218
• Smallest number with exactly n^2 divisors.at n=13A061707
• Smallest number whose square has (2n - 1)^2 divisors.at n=19A061708
• Number of n-digit positive integers with all digits distinct.at n=7A073531
• a(1) = 1; a(n) = n * Sum_{k=1..n-1} a(k).at n=8A074143
• One half of fourth column of triangle A075181.at n=5A075184
• a(n) = n^4 - n^3.at n=36A085537
• a(n) = n*(n + 1)^3.at n=35A085540
• Triangle read by rows: T(n,k) is the number of n-bead necklaces with exactly k different colored beads.at n=53A087854
• a(1) = 3, a(n) = smallest multiple of a(n-1) such that 10*a(n) + 1 is prime.at n=13A089325
• Triangle read by rows: T(n,m) = A094310(n,m)*A120070(n+1,m), 1 <= m <= n.at n=43A165969
• Expansion x^2*cotan(x)/(exp(x^2*cotan(x))-1) = Sum_{n>=0} a(n)*x^n/(n+1)!^2.at n=8A199541
• Triangular array read by rows. T(n,k) is the number of connected endofunctions on {1,2,...,n} that have exactly k nodes in the unique cycle of its digraph representation.at n=42A201685
• (n-1)-st elementary symmetric function of the first n terms of the periodic sequence (2,3,2,3,2,3,...).at n=13A203232