67830

Appears in sequences

• Expansion of 1/(1-4*x)^(15/2).at n=4A020926
• Expansion of (1-4*x)^(21/2).at n=4A020933
• Products of exactly 6 distinct primes.at n=8A067885
• Sides of integer Heronian triangles [A068967(n), prime(A068967(n)), a(n)] with area A068969(n).at n=30A068968
• Numbers with six distinct prime divisors.at n=9A074969
• Largest squarefree number that divides A077175(n).at n=5A077176
• A sequence derived from pentagonal numbers, or a Stirling number of the first kind matrix.at n=27A094952
• Largest squarefree number that divides A101177(n).at n=5A101178
• Triangle of coefficients of square of Hermite polynomials divided by 2^n with argument sqrt(x/2).at n=40A111595
• Fifth column (m=4) of unsigned triangle A111595.at n=4A111778
• The 3rd Witt transform of A000217.at n=16A147618
• Records in A152235.at n=41A152452
• Numbers n such that sigma(n) = 15*phi(n) (where sigma=A000203, phi=A000010).at n=5A171260
• a(n) = n*(n+1)*(5*n+1)/3.at n=34A174814
• Period of the decimal expansion of 1/F as F runs through the Fibonacci numbers greater than 1 and not divisible by 2 or 5.at n=16A175550
• Period of the decimal representation of 1/Fibonacci(n).at n=31A175561
• Antidiagonal sums of the convolution array A213778.at n=33A213780
• Triangle read by rows: T(n,k) = binomial(k,n-k)*binomial(n+2*k,n+k) /(n+k+1), n>=0, 0<=k<=n.at n=51A243163
• Numbers k such that usigma(k) >= 3*k, where usigma(k) = sum of unitary divisors of k (A034448).at n=8A285615
• a(n) is the smallest number k such that psi(k) = n*phi(k) where psi(k) is Dedekind psi function (A001615) and phi(k) is Euler totient function (A000010), or 0 if no such k exists.at n=14A291051