369189domain: NAppears in sequencesSum of numbers that can be written as t*n + u*(n+1) for nonnegative integers t,u in exactly four ways.at n=16A076457Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 5 ones in any 5 X 5 X 5 subtriangle.at n=12A153944