322885domain: NAppears in sequencesConvolution of the (signless) central Stirling numbers of the first kind (A187646) and the central Stirling numbers of the second kind (A007820).at n=5A187659Number of 3 X n 0..2 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing.at n=7A224263