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Write n in 4-ary, sort digits into increasing order.
9

%I #18 Aug 07 2024 15:40:49

%S 0,1,2,3,1,5,6,7,2,6,10,11,3,7,11,15,1,5,6,7,5,21,22,23,6,22,26,27,7,

%T 23,27,31,2,6,10,11,6,22,26,27,10,26,42,43,11,27,43,47,3,7,11,15,7,23,

%U 27,31,11,27,43,47,15,31,47,63,1,5,6,7,5,21,22,23,6,22,26,27

%N Write n in 4-ary, sort digits into increasing order.

%H Seiichi Manyama, <a href="/A319652/b319652.txt">Table of n, a(n) for n = 0..4095</a>

%p a:= n-> (l-> add(l[-i]*4^(i-1), i=1..nops(l)))(sort(convert(n, base, 4))):

%p seq(a(n), n=0..75); # _Alois P. Heinz_, Aug 07 2024

%t Table[FromDigits[Sort[IntegerDigits[n, 4]], 4], {n, 0, 100}] (* _Paolo Xausa_, Aug 07 2024 *)

%o (Ruby)

%o def A(k, n)

%o (0..n).map{|i| i.to_s(k).split('').sort.join.to_i(k)}

%o end

%o p A(4, 100)

%o (PARI) a(n) = fromdigits(vecsort(digits(n, 4)), 4); \\ _Michel Marcus_, Sep 25 2018

%Y b-ary: A038573 (b=2), A038574 (b=3), this sequence (b=4), A319653 (b=5), A319654 (b=6), A319655 (b=7), A319656 (b=8), A319657 (b=9), A004185 (b=10).

%Y Cf. A165012.

%K nonn,base

%O 0,3

%A _Seiichi Manyama_, Sep 25 2018