21911761

Appears in sequences

• n in base 8 is a palindromic square.at n=31A029806
• Number of (n+1)X(3+1) 0..1 arrays with no element having a strict majority of its horizontal and vertical neighbors equal to one.at n=8A231972
• Base-8 representation of a(n) is the concatenation of the base-8 representations of 1, 2, ..., n, n-1, ..., 1.at n=5A260858
• a(n) = sigma_3(n)^2.at n=15A356534