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%I #12 Apr 25 2021 01:25:56
%S 820,821,825,826,829,830,831,833,867,869,870,871,874,875,879,880,901,
%T 902,906,907,910,911,912,914,921,923,924,925,937,938,939,941,1245,
%U 1247,1248,1249,1261,1262,1263,1265,1272,1274,1275
%N Numbers whose base-3 representation has exactly 7 runs.
%t Select[Range[1300],Length[Split[IntegerDigits[#,3]]]==7&] (* _Harvey P. Dale_, Feb 23 2011 *)
%Y Cf. A007089.
%K nonn,base
%O 1,1
%A _Clark Kimberling_