148953domain: NAppears in sequencesQuadrinomial coefficients: C(2+n,n) + C(3+n,n) + C(4+n,n).at n=40A005718Number of 4 X n 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.at n=27A229447