a(1)=0, a(1)=1, a(n+2)=abs(concatenate(a(n+1)a(n))-concatenate(a(n)a(n+1))).

A070823

a(1)=0, a(1)=1, a(n+2)=abs(concatenate(a(n+1)a(n))-concatenate(a(n)a(n+1))).

Terms

    a(0) =0a(1) =1a(2) =9a(3) =72a(4) =243a(5) =47871a(6) =23523372

External references