2021980

Appears in sequences

• Expansion of (1+x^3*C)*C^3, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.at n=12A071728
• a(n) = a(n-1) + a(n-2) + 2*a(floor(n/2)) + 3*a(floor(n/3)) + ... + n*a(floor(n/n)), where a(0) = 1, a(1) = 1, a(2) = 1.at n=25A298369