635595

Appears in sequences

• a(n) = 3*a(n-1) - 2*a(n-2) - a(n-3) + a(n-4) with n>3, a(0)=1, a(1)=2, a(2)=3, a(3)=6.at n=26A131269
• Number of nX4 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X5 binary array having nonzero determinant, with rows and columns of the latter in lexicographically nondecreasing order.at n=6A227556
• T(n,k)=Number of nXk 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X(k+1) binary array having nonzero determinant, with rows and columns of the latter in lexicographically nondecreasing order.at n=48A227558