82639

Appears in sequences

• Number of subsequences of {1..n} such that all differences of pairs of terms are distinct (i.e., number of Golomb rulers on {1..n}).at n=28A054578
• a(2*n+1) = 9*a(n), a(2*n+2) = 10*a(n) + a(n-1).at n=40A116555