a(n) = 99*(n+1)*binomial(n+5,12).

Terms

a(0) =792a(1) =11583a(2) =90090a(3) =495495a(4) =2162160a(5) =7963956a(6) =25729704a(7) =74826180a(8) =199536480a(9) =494684190a(10) =1152323172a(11) =2543258718a(12) =5354228880a(13) =10811423700a(14) =21034470600a(15) =39583049220a(16) =72282089880a(17) =128442439125a(18) =222633561150a(19) =377215163325a(20) =625897752480