60420

Appears in sequences

• Numbers k such that 3k - 1 divides 3^k - 1.at n=27A273614
• Triangle, read by rows, defined by recurrence: T(n,k) = T(n-1,k-1) + (-1)^k * (2 * k + 1) * T(n-1,k) for 0 < k < n with initial values T(n,0) = T(n,n) = 1 for n >= 0 and T(i,j) = 0 if j < 0 or j > i.at n=47A346083
• Expansion of 1/((1-x) * (1+3*x) * (1-5*x)).at n=7A383637