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A370859
Numbers m such that c(0) < c(1) > c(2), where c(k) = number of k's in the ternary representation of m.
9
1, 4, 10, 12, 13, 14, 16, 22, 31, 32, 34, 37, 38, 39, 40, 41, 42, 43, 46, 48, 49, 58, 64, 66, 67, 85, 91, 93, 94, 95, 97, 103, 109, 111, 112, 113, 115, 117, 118, 119, 120, 121, 122, 123, 124, 125, 127, 129, 130, 131, 133, 139, 145, 147, 148, 149, 151, 157
OFFSET
1,2
EXAMPLE
The ternary representation of 16 is 121, for which c(0)=0 < c(1)=2 > c(2)=1.
MAPLE
filter:= proc(n) local L, m;
L:= convert(n, base, 3); m:= numboccur(1, L);
numboccur(0, L) < m and numboccur(2, L) < m
end proc:
select(filter, [$1 .. 200]); # Robert Israel, Mar 03 2024
MATHEMATICA
Select[Range[1000], DigitCount[#, 3, 0] < DigitCount[#, 3, 1] > DigitCount[#, 3, 2] &]
KEYWORD
nonn,base
AUTHOR
Clark Kimberling, Mar 03 2024
STATUS
approved