47880

Appears in sequences

• 4-dimensional analog of centered polygonal numbers: a(n) = n(n+1)*(n^2+n+4)/12.at n=27A006007
• a(n) = (n + 1)*(n + 2)*(n + 4)*(n + 8)*(n + 15)/120.at n=17A006636
• Triangle read by rows, the Bell transform of (n+2)!/2 without column 0.at n=23A046089
• Number of nonempty subsets of {1,2,...,n} in which exactly 3/4 of the elements are <= (n+1)/3.at n=28A048042
• Number of nonempty subsets of {1,2,...,n} in which exactly 3/4 of the elements are <= (n+2)/3.at n=28A048075
• Number of nonempty subsets of {1,2,...,n} in which exactly 3/4 of the elements are <= (n+3)/3.at n=28A048086
• Number of walks of length n on square lattice, starting at origin, staying on points with x >= 0, y <= x.at n=9A060900
• Numbers expressible as (a^2-1)(b^2-1) in at least 2 distinct ways (b>=a>1).at n=27A063067
• Numbers n such that sigma(n)^2 > 9*sigma_2(n) where sigma_2(n) is the sum of squares over the divisors of n.at n=26A068378
• Numbers k such that the number of steps to reach 1 in '3x+1' problem equals tau(k), the number of divisors of k.at n=49A070980
• Numbers k such that 2^k - 1 is divisible by (k-1).at n=31A087965
• Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A071665/A071666.at n=14A089872
• Numbers that can be expressed as the difference of the squares of primes in exactly six distinct ways.at n=26A092002
• n! times sum of Farey fractions of order n.at n=6A093593
• a(n) is the smallest number k such that Fibonacci(k) is a multiple of primorial(n).at n=11A114419
• a(n) is the smallest number k such that Fibonacci(k) is a multiple of primorial(n).at n=12A114419
• Irregular triangle read by rows T(n,k) (n>=1, 0<=k<=n(n-1)/2) giving the total number of connected components in all subgraphs (V,E') with |E'|=k of the complete labeled graph K_n=(V,E).at n=46A125205
• Highly abundant numbers (A002093) that are not Harshad numbers (A005349).at n=3A128702
• Unsigned fourth column (k=3) of triangle A136656 divided by 8.at n=4A136660
• a(n) = n*(n+1)*(n+2)*(n+3)/3.at n=18A162668