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A319651
Largest number having in its ternary representation the same number of 0's, 1's and 2's as n.
9
0, 1, 2, 3, 4, 7, 6, 7, 8, 9, 12, 21, 12, 13, 22, 21, 22, 25, 18, 21, 24, 21, 22, 25, 24, 25, 26, 27, 36, 63, 36, 39, 66, 63, 66, 75, 36, 39, 66, 39, 40, 67, 66, 67, 76, 63, 66, 75, 66, 67, 76, 75, 76, 79, 54, 63, 72, 63, 66, 75, 72, 75, 78, 63, 66, 75, 66, 67, 76, 75, 76
OFFSET
0,3
LINKS
FORMULA
n <= a(n) < 3n. - Charles R Greathouse IV, Aug 07 2024
MATHEMATICA
Table[FromDigits[ReverseSort[IntegerDigits[n, 3]], 3], {n, 0, 100}] (* Paolo Xausa, Aug 07 2024 *)
PROG
(Ruby)
def A(k, n)
(0..n).map{|i| i.to_s(k).split('').sort.reverse.join.to_i(k)}
end
p A(3, 100)
(PARI) a(n) = fromdigits(vecsort(digits(n, 3), , 4), 3); \\ Michel Marcus, Sep 25 2018
(Python)
from gmpy2 import digits
def A319651(n):
return int(''.join(sorted(digits(n, 3), reverse=True)), 3) # Chai Wah Wu, Sep 26 2018
CROSSREFS
Base b: A073138 (b=2), this sequence (b=3), A319720 (b=4), A319722 (b=5), A319723 (b=6), A319724 (b=7), this sequence (b=8), A319726 (b=9), A004186 (b=10).
Cf. A038574.
Sequence in context: A132075 A265364 A265363 * A373185 A340632 A074846
KEYWORD
nonn,base,look,easy
AUTHOR
Seiichi Manyama, Sep 25 2018
STATUS
approved