75101

Appears in sequences

• Numbers k such that phi(sigma(phi(k))) = sigma(k).at n=11A066462
• Let r, s, t, u be four permutations of the set { 1, 2, 3, ..., n }; a(n) = minimal value of Sum_{i=1..n} r(i)*s(i)*t(i)*u(i).at n=18A070736