139230

Appears in sequences

• Coefficients of Chebyshev polynomials.at n=24A005583
• Number of exterior points formed by extending diagonals of n-gon in general position.at n=33A005701
• Number of scalars which can be constructed from the Riemann tensor and metric tensor in n dimensions.at n=35A050297
• Numbers k such that phi(k) < k/5.at n=16A066765
• Ninth column (m=8) of (1,3)-Pascal triangle A095660.at n=11A095664
• Where A098018(k)=n.at n=18A098869
• a(n) = n*(n-1)*(n-2)*(n+3)/12.at n=36A117662
• Numbers n > 0 such that n^6 + 1091 and n^6 + 1093 are both prime.at n=1A181114
• Numbers with prime factorization pqrstu^2.at n=12A189985
• Let s(k) denote the sum of the even proper divisors of k. The sequence lists the pairs of numbers (x, y) such that s(x) = y and s(y) = x.at n=20A279812
• List of ordered pairs (x, y) from A279812.at n=22A279950
• Numbers m having greatest prime power divisor d such that d is smaller than the difference between m and the largest prime smaller than m and d is smaller than the difference between m and twice the largest prime smaller than m/2.at n=27A290290
• Numbers k that are norm-superabundant in Gaussian integers, i.e., A103230(m)/m^2 < A103230(k)/k^2 for all m < k.at n=16A332321
• Dirichlet g.f.: Product_{k>=2} 1 / (1 - k^(-s))^binomial(k+3,4).at n=38A344204
• Indices k of records of low value in the ratios A348158(k)/k.at n=6A348159
• a(n) = 60*binomial(3*n,n)/(n+2).at n=6A386517
• a(n) is the first number with a total of exactly n 3's in the decimal digits of its divisors.at n=36A387464