The number of n-digit numbers in A264847 (pluritriangular numbers).

Terms

a(0) =0a(1) =4a(2) =8a(3) =19a(4) =50a(5) =142a(6) =408a(7) =1186a(8) =3498a(9) =10401a(10) =31139a(11) =93728a(12) =283377a(13) =859939a(14) =2617798a(15) =7990517a(16) =24447214a(17) =74950315a(18) =230198869a(19) =708160711a(20) =2181656006a(21) =6729833482a(22) =20784165689a(23) =64257670873a(24) =198857204708a(25) =615951476925