%I
%S 1,12,123,1235,12356,123567,12356710,1235671011,123567101113,
%T 12356710111314,1235671011131415,123567101113141517,
%U 12356710111314151719,1235671011131415171921,123567101113141517192122
%N Concatenation of the first n squarefree numbers A005117.
%F Prepend 1 to the terms of A159902(n1).
%Y Cf. A005117.
%K nonn,base,less
%O 1,2
%A _Jaroslav Krizek_, Apr 25 2009
%E Slightly edited by _R. J. Mathar_, Apr 28 2009
