%I #29 Sep 08 2022 08:44:50
%S 1,2,4,8,61,32,64,821,652,521,4210,8420,9640,9821,86431,87632,66553,
%T 732110,644221,885422,8765410,9752210,9444310,8888630,77766211,
%U 55443332,88766410,877432211,866554432,987653210,8774432110,8876444321
%N Arrange digits of 2^n in descending order.
%H Alois P. Heinz, <a href="/A028910/b028910.txt">Table of n, a(n) for n = 0..3321</a>
%p a:= n-> parse(cat(sort(convert(2^n, base, 10), `>`)[])):
%p seq(a(n), n=0..50); # _Alois P. Heinz_, Jan 21 2020
%t FromDigits[Reverse[Sort[IntegerDigits[#]]]]&/@(2^Range[0,40]) (* _Harvey P. Dale_, Mar 06 2020 *)
%o (Magma) [Seqint(Sort(Intseq(2^n))):n in [0..31]]; // _Marius A. Burtea_, Oct 06 2019
%o (Python)
%o def A028910(n):
%o return int(''.join(sorted(str(2**n),reverse=True))) # _Chai Wah Wu_, Feb 19 2021
%Y The following are parallel families: A000079 (2^n), A004094 (2^n reversed), A028909 (2^n sorted up), A028910 (2^n sorted down), A036447 (double and reverse), A057615 (double and sort up), A263451 (double and sort down); A000244 (3^n), A004167 (3^n reversed), A321540 (3^n sorted up), A321539 (3^n sorted down), A163632 (triple and reverse), A321542 (triple and sort up), A321541 (triple and sort down).
%K nonn,base
%O 0,2
%A _N. J. A. Sloane_
%E More terms from _Patrick De Geest_, Apr 15 1998
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