1132408domain: NAppears in sequencesNumber of planar triangular n X n X n nonnegative integer grids with mirror symmetry about one altitude with every similarly oriented 5 X 5 X 5 subtriangle summing to 14.at n=4A154091Number of (n+4) X 9 0..1 matrices with each 5 X 5 subblock idempotent.at n=28A224687