180960

Appears in sequences

• Positive integers n such that n^2 = (x^4 - y^4)*(z^4 - t^4) where x>y and z>t are distinct pairs of integers with gcd(x,y)=gcd(z,t)=1.at n=18A147856
• Numbers with prime factorization pqrst^5.at n=29A190383
• a(n) = phi(Lucas(n)).at n=26A197218
• Number of regular tetrahedra in an n-node-per-edge tetrahedral grid.at n=33A269747
• a(n) = 2^n - Sum_{m=0..n} binomial(n/gcd(n,m), m/gcd(n,m)) = 2^n - A082906.at n=17A271834
• Number of 4Xn 0..2 arrays with no element equal to any value at offset (-2,0) (-1,2) or (0,-2) and new values introduced in order 0..2.at n=8A275567
• Lesser of modified exponential amicable pairs.at n=15A323758