66746

Appears in sequences

• Smallest k > 0 such that k + F_n are all primes, where F_n is the n-th Fermat number.at n=6A063898
• a(n) = one-half of the number of cells in the central rectangle of the graph described in row 2n+1 of A333288.at n=37A337640
• Place n equally spaced points around the circumference of a circle and then, for each pair of points, draw two distinct circles, whose radii are the same as the first circle, such that both points lie on their circumferences. The sequence gives the total number of (curved) edges formed.at n=22A371375