123621

Appears in sequences

• Number of (w,x,y,z) with all terms in {0,...,n} and at least one of these conditions holds: w<R, x<R, y>R, z>R, where R = max{w,x,y,z} - min{w,x,y,z}.at n=18A212753
• Number of (n+3) X 10 0..1 matrices with each 4 X 4 subblock idempotent.at n=20A224567