%I #4 Aug 14 2019 16:53:48
%S 16,727,70207,7002007,700020007,70000200007,7000002000007,
%T 700000020000007,70000000200000007,7000000002000000007,
%U 700000000020000000007,70000000000200000000007
%N 10^n*(2+7*10^n)+7.
%t Join[{16},FromDigits/@Table[Join[{7},PadRight[{},n,0],{2},PadRight[{},n,0],{7}],{n,0,10}]] (* _Harvey P. Dale_, Aug 14 2019 *)
%K easy,nonn
%O 0,1
%A _Jason Earls_, Dec 17 2009