63886

Appears in sequences

• a(n) = (Sum{1/C(i,j)})*LCM{C(i,j)}, 0 <= j <= i <= n.at n=10A025539
• Coefficient of q^3 in nu(n), where nu(0)=1, nu(1)=b and, for n>=2, nu(n)=b*nu(n-1)+lambda*(1+q+q^2+...+q^(n-2))*nu(n-2) with (b,lambda)=(1,1).at n=17A074083
• Matrix square of triangle A107721, read by rows.at n=40A107722
• Number of LDU's in all skew Dyck paths of semilength n.at n=10A128737
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 1, 0), (0, 1, -1), (1, 0, 1), (1, 1, -1)}.at n=9A149452
• Expansion of 1/sqrt((1 - x + x^3)^2 + 4*x^4).at n=20A375292