187925

Appears in sequences

• a(n) = 3*a(n-1)-a(n-2)-2*a(n-3)+a(n-4), n>5.at n=15A107298
• Number of (n+1)X(n+1) -11..11 symmetric matrices with every 2X2 subblock having sum zero and one, two or three distinct values.at n=8A211714