%I
%S 1,21,123,4321,12345,654321,1234567,87654321,123456789,10987654321,
%T 1234567891011,121110987654321,12345678910111213,1413121110987654321,
%U 123456789101112131415
%N Append n to previous term, reverse alternate terms.
%D Felice Russo, A set of new Smarandache functions, sequences and conjectures in number theory, American Research Press 2000
%Y A000422, A007908.
%K easy,base,nonn
%O 1,2
%A _Felice Russo_, Feb 25 2000
