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A039044
Numbers whose base-7 representation has the same number of 3's and 4's.
1
0, 1, 2, 5, 6, 7, 8, 9, 12, 13, 14, 15, 16, 19, 20, 25, 31, 35, 36, 37, 40, 41, 42, 43, 44, 47, 48, 49, 50, 51, 54, 55, 56, 57, 58, 61, 62, 63, 64, 65, 68, 69, 74, 80, 84, 85, 86, 89, 90, 91, 92, 93, 96, 97, 98, 99, 100, 103, 104, 105, 106, 107, 110, 111, 112, 113, 114
OFFSET
1,3
LINKS
MAPLE
filter:= proc(n) local L;
L:= convert(n, base, 7);
numboccur(3, L)=numboccur(4, L)
end proc:
select(filter, [$0..1000]); # Robert Israel, Feb 01 2021
MATHEMATICA
Select[Range[0, 200], DigitCount[#, 7, 3]==DigitCount[#, 7, 4]&] (* Harvey P. Dale, Feb 07 2019 *)
CROSSREFS
Cf. A007093.
Sequence in context: A287440 A111175 A047326 * A212441 A182783 A084852
KEYWORD
nonn,base,easy
STATUS
approved