Pendulum numbers: alternately append n to beginning or end of previous term.

A053063

Pendulum numbers: alternately append n to beginning or end of previous term.

Terms

    a(0) =1a(1) =21a(2) =213a(3) =4213a(4) =42135a(5) =642135a(6) =6421357a(7) =86421357a(8) =864213579a(9) =10864213579

External references