387515

Appears in sequences

• a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2*n - 3 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = a(3) = 1.at n=19A049932
• Number of difference sets of subsets of {1,2,...,n}, i.e., the size of {D(A) : A subset [n] }, where D(A)={a_i-a_j : a_i>a_j and a_i,a_j in A}.at n=27A067247