Positive integers k such that f(k)+f(k)=concatenation of k and k, where f(k)=k(k+3)/2 (A000096).

A099150

Positive integers k such that f(k)+f(k)=concatenation of k and k, where f(k)=k(k+3)/2 (A000096).

Terms

    a(0) =8a(1) =98a(2) =998a(3) =9998a(4) =99998a(5) =999998a(6) =9999998a(7) =99999998a(8) =999999998a(9) =9999999998a(10) =99999999998a(11) =999999999998

External references