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%I #12 Jul 28 2023 21:34:48
%S 1,2,3,4,5,6,11,19,21,27,29,37,45,78,135,150,192,207,264,315,321,550,
%T 950,1050,1056,1344,1350,1450,1850,2208,2250,3851,6652,7353,7395,9411,
%U 9453,10154,12955,15456,15462,15750,15756,26961,46569,51471,51477,51765,51771
%N Numbers in which all pairs of consecutive base-7 digits differ by 3.
%t Join[Range[6],Select[Range[27000],Union[Abs[Differences[IntegerDigits[#,7]]]] =={3}&]] (* _Harvey P. Dale_, Apr 21 2011 *)
%K nonn,base
%O 1,2
%A _Clark Kimberling_