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%I #15 Feb 05 2022 02:15:15
%S 2,1,0,7,4,1,6,3,0,25,16,7,22,13,4,19,10,1,24,15,6,21,12,3,18,9,0,79,
%T 52,25,70,43,16,61,34,7,76,49,22,67,40,13,58,31,4,73,46,19,64,37,10,
%U 55,28,1,78,51,24,69,42,15,60,33,6,75,48,21,66,39,12,57,30
%N Write in base k, complement, reverse. Case k = 3.
%H Harvey P. Dale, <a href="/A284797/b284797.txt">Table of n, a(n) for n = 0..1000</a>
%e a(9) = 25 because 9 in base 3 is 100, its complement in base 3 is 122 and the digit reverse is 221 that is 25 in base 10.
%p P:=proc(q,h) local a,b,k,n; print(h-1); for n from 1 to q do a:=convert(n,base,h); b:=0;
%p for k from 1 to nops(a) do a[k]:=h-1-a[k]; b:=h*b+a[k]; od; print(b); od; end: P(10^2,3);
%t Table[FromDigits[Reverse[2-IntegerDigits[n,3]],3],{n,0,70}] (* _Harvey P. Dale_, Sep 08 2019 *)
%o (Python)
%o from gmpy2 import digits
%o def A284797(n): return -int((s:=digits(n,3)[::-1]),3)-1+3**len(s) # _Chai Wah Wu_, Feb 04 2022
%Y Cf. A036044, A267193, A284798.
%K nonn,base,easy
%O 0,1
%A _Paolo P. Lava_, Apr 03 2017