177242

Appears in sequences

• Denominators of the first differences of 1/(n^2 + 1).at n=20A033466
• a(0)=1; a(n+1) = 1 + f(a(n))^2, where f(x) is the largest prime factor of x (A006530).at n=7A072268
• Integers of the form k^2 + 1, where k >= 1, that are the product of two other integers of the form k^2 + 1, where k >= 1.at n=29A372496