84273

Appears in sequences

• Numerators of 1/2 + sum(chi(p)^(4*n / (p-1))/p) where the sum is over primes p of the form 4k+1 such that p-1 divides 4*n and the numbers chi(p) are given by A002172.at n=9A274398
• a(n) is the number of distinct radii of circles passing through at least three points in a square grid of n X n points.at n=27A357301