140500

Appears in sequences

• Number of solutions of +- 1 +- 2 +- ... +- (n-1) +- n = 0 in which the partial sums +- 1 +- ... +- k (1<=k<=n) are all distinct.at n=35A015818
• The common value of sigma_2 for square-amicable numbers, sigma_2(m)=sigma_2(n), m<n.at n=27A110929