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%I #13 Sep 13 2020 16:19:03
%S 4,32,200,207,214,221,228,235,242,1376,1432,1488,1544,1600,1656,1712,
%T 9608,9657,9706,9755,9804,9853,9902,9958,10007,10056,10105,10154,
%U 10203,10252,10308,10357,10406,10455,10504,10553,10602
%N Base-7 palindromes that start with 4.
%H Harvey P. Dale, <a href="/A043018/b043018.txt">Table of n, a(n) for n = 1..10000</a>
%t Join[{4},FromDigits[#,7]&/@Select[Flatten[Table[Join[{4},#,{4}]&/@ Tuples[ Range[ 0,6],n],{n,0,3}],1],#==Reverse[#]&]] (* _Harvey P. Dale_, Sep 13 2020 *)
%K nonn,base
%O 1,1
%A _Clark Kimberling_