a(n) = (n+1)*binomial(n+8, 8).

Terms

a(0) =1a(1) =18a(2) =135a(3) =660a(4) =2475a(5) =7722a(6) =21021a(7) =51480a(8) =115830a(9) =243100a(10) =481338a(11) =906984a(12) =1637610a(13) =2848860a(14) =4796550a(15) =7845024a(16) =12503007a(17) =19468350a(18) =29683225a(19) =44401500a(20) =65270205a(21) =94427190a(22) =134617275a(23) =189329400a(24) =262957500a(25) =360988056a(26) =490217508a(27) =659002960a(28) =877549860a(29) =1158240600