503440

Appears in sequences

• From the enumeration of corners.at n=14A006332
• If X_1,...,X_n is a partition of a 2n-set X into 2-blocks then a(n) is equal to the number of 4-subsets of X containing none of X_i, (i=1,...,n).at n=27A130810
• Triangle read by rows: the reversed x = 1+q Narayana triangle at m=3.at n=40A243663
• Number of (n+2)X(3+2) 0..1 arrays with every 3X3 subblock sum of the two medians of the diagonal and antidiagonal minus the sum of the medians of the central row and column nondecreasing horizontally and vertically.at n=2A254993
• T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with every 3X3 subblock sum of the two medians of the diagonal and antidiagonal minus the sum of the medians of the central row and column nondecreasing horizontally and vertically.at n=12A254998
• G.f. satisfies A(x) = 1 + x^4*A(x)^5*(1 + x*A(x)).at n=26A365731