Number of n X 4 0..2 matrices with row sums 4 and column sums n up to permutations of rows.

Terms

a(0) =1a(1) =1a(2) =10a(3) =30a(4) =117a(5) =345a(6) =1042a(7) =2746a(8) =7063a(9) =16759a(10) =38440a(11) =83476a(12) =175473a(13) =354105a(14) =694278a(15) =1318222a(16) =2440888a(17) =4402852a(18) =7770908a(19) =13418156a(20) =22734824a(21) =37807500a(22) =61839510a(23) =99526422a(24) =157858478a(25) =246864782a(26) =381087734a(27) =580990046a(28) =875572808a(29) =1304930876