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A039111
Numbers whose base-9 representation has the same number of 7's and 8's.
1
0, 1, 2, 3, 4, 5, 6, 9, 10, 11, 12, 13, 14, 15, 18, 19, 20, 21, 22, 23, 24, 27, 28, 29, 30, 31, 32, 33, 36, 37, 38, 39, 40, 41, 42, 45, 46, 47, 48, 49, 50, 51, 54, 55, 56, 57, 58, 59, 60, 71, 79, 81, 82, 83, 84, 85, 86, 87, 90, 91, 92, 93, 94, 95, 96, 99, 100, 101, 102
OFFSET
1,3
MATHEMATICA
okQ[n_]:=Module[{idn9=IntegerDigits[n, 9]}, Count[idn9, 7]==Count[idn9, 8]]
Select[Range[0, 110], okQ] (* Harvey P. Dale, Dec 14 2010 *)
Select[Range[0, 120], DigitCount[#, 9, 7]==DigitCount[#, 9, 8]&] (* Harvey P. Dale, Nov 03 2024 *)
CROSSREFS
Cf. A007095.
Sequence in context: A039204 A039153 A272574 * A037475 A354047 A031487
KEYWORD
nonn,base,easy,changed
STATUS
approved