399000

Appears in sequences

• Half of the height of the right trapezoidal gnomon (of the derivative of Y=X^5).at n=19A281999
• Numbers that are product of a hexagonal number (A000384) and a square pyramidal numbers (A000330) in at least two ways.at n=39A306121
• a(n) is the sum of the divisors of n!-1.at n=7A366757
• E.g.f. A(x) satisfies A(x) = (1+x) * exp(x^2 * (1+x)^2 * A(x)).at n=7A389819