81975

Appears in sequences

• a(n) = Sum_{i=1..floor((n+1)/4)} a(2*i-1) * a(n-2*i+1), with a(1)=3 and a(2)=a(3)=1.at n=12A024737
• Floor[X/Y] where X = concatenation of (n+1)-st odd number through the 2n-th odd number and Y = concatenation of first n odd numbers.at n=4A067093
• Number of reducible Boolean polynomials of degree n with constant term 1.at n=20A169914
• Number of (5+2) X (n+2) 0..3 arrays with every consecutive three elements in every row and diagonal having exactly two distinct values, and in every column and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order.at n=33A252724