137780

Appears in sequences

• a(n) = Sum_{k=0..2n} (k+1) * A027082(n, 2n-k).at n=10A027107
• Smallest integer m > n such that both n*m and (n+1)*(m+1) are squares.at n=20A212651
• Principal diagonal of the convolution array A213838.at n=29A213839
• a(n) = n * (4*n + 3)^2.at n=20A322675
• Expansion of g.f.: (1 + x - 2*x^2 + 2*x^4)/((1-x)*(1-3*x^2)).at n=21A358027