1528920

Appears in sequences

• a(n) = (2n-1)!! * Sum_{k=0..n-1}(-1)^k/(2k+1).at n=8A024199
• The ED4 array read by antidiagonals.at n=28A167584
• A triangle related to the GF(z) formulas of the rows of the ED4 array A167584.at n=35A167594
• Number of (n+1) X 4 0..2 arrays with no 2 X 2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases in its adjacent leftward or upward neighbors.at n=6A206272
• Number of (n+1) X 8 0..2 arrays with no 2 X 2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases in its adjacent leftward or upward neighbors.at n=2A206276