a(n) = Sum_{m=1..n} (Sum_{k=1..m} (Sum_{j=1..k} j^n)).

A349116

a(n) = Sum_{m=1..n} (Sum_{k=1..m} (Sum_{j=1..k} j^n)).

Terms

    a(0) =1a(1) =7a(2) =57a(3) =605a(4) =7990a(5) =126378a(6) =2331462a(7) =49183590a(8) =1168343775a(9) =30871159429a(10) =898302280271

External references