OFFSET
1,2
MATHEMATICA
With[{s=21^Range[0, 100]}, Table[SelectFirst[s, Take[IntegerDigits[ #], IntegerLength[ n]] == IntegerDigits[ n]&], {n, 30}]]//Quiet (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 24 2020 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Daniel Mondot (dmondot(AT)gmail.com), Sep 18 2010
STATUS
approved