240864

Appears in sequences

• Determinant of the n X n matrix whose element (i,j) equals the |i-j|-th composite number, or 1 if i=j.at n=6A071080
• a(n) is the least number k such that the equation phi(x) = k has exactly n solutions and the arithmetic mean of these solutions is an integer, or -1 if no such number exists.at n=33A389860