n-th derivative of ((x^x)^x)^x at x=1.

Terms

a(0) =1a(1) =1a(2) =6a(3) =27a(4) =156a(5) =1110a(6) =8322a(7) =70098a(8) =646272a(9) =6333336a(10) =66712680a(11) =745731360a(12) =8780828328a(13) =108873486072