a(n) = 90*binomial(n,6) + 90*binomial(n,5) + 54*binomial(n,4) + 24*binomial(n,3) + 9*binomial(n,2) + 3*n + 1.

A382640

a(n) = 90*binomial(n,6) + 90*binomial(n,5) + 54*binomial(n,4) + 24*binomial(n,3) + 9*binomial(n,2) + 3*n + 1.

Terms

    a(0) =1a(1) =4a(2) =16a(3) =61a(4) =217a(5) =706a(6) =2074a(7) =5461a(8) =12961a(9) =28072a(10) =56236a(11) =105469a(12) =187081a(13) =316486a(14) =514102a(15) =806341a(16) =1226689a(17) =1816876a(18) =2628136a(19) =3722557a(20) =5174521a(21) =7072234a(22) =9519346a(23) =12636661a(24) =16563937a(25) =21461776a(26) =27513604a(27) =34927741a(28) =43939561a(29) =54813742

External references