66400

Appears in sequences

• Numbers n such that every digit of both n and n^2 contains a loop (only digits 0,4,6,8,9 in n and n^2).at n=20A107626
• Numbers k such that k and k^2 use only the digits 0, 4, 6, 8 and 9.at n=21A136956
• a(n) = ((4+sqrt(3))*(1+sqrt(3))^n + (4-sqrt(3))*(1-sqrt(3))^n)/2.at n=10A162559
• Number of right isosceles triangles that can be formed from the n^2 points of n X n grid of points (or geoboard).at n=19A187452
• a(n) = [x^n] (Sum_{k=0..n} (k+1)!*x^k)/(Sum_{k=0..n} (k+1)!*(-x)^k).at n=7A303566