%I #17 Apr 12 2022 09:53:26
%S 1,2,3,7,17,27,4,14,24,1,11,21,31,8,18,28,5,15,25,2,12,22,32,9,19,29,
%T 6,16,26,3,13,23,33,67,167,267,37,137,237,7,107,207,307,77,177,277,47,
%U 147,247,17,117,217,317,87,187,287,57,157,257,27,127,227,327,97,197,297,34
%N a(n) = digit reversal of 3*n, divided by 3.
%C If n is a multiple of 10, then a(n) = a(n/10); if n is not a multiple of 10, then a(a(n)) = n.
%H Harvey P. Dale, <a href="/A083822/b083822.txt">Table of n, a(n) for n = 1..1000</a>
%e a(25) = reverse(3*25)/3 = reverse(75)/3 = 57/3 = 19.
%t Table[FromDigits[Reverse[IntegerDigits[3n]]]/3,{n,70}] (* _Harvey P. Dale_, May 19 2015 *)
%t IntegerReverse[3*Range[70]]/3 (* _Harvey P. Dale_, Apr 12 2022 *)
%o (PARI) {for(n=1,70,k=3*n; rev=0; while(k>0,d=divrem(k,10); k=d[1]; rev=10*rev+d[2]); print1(rev/3,","))}
%o (PARI) apply( A083822(n)=fromdigits(Vecrev(digits(3*n)))/3, [0..99]) \\ _M. F. Hasler_, May 21 2021
%Y Cf. A083823, A083824, A083825.
%K base,easy,nonn
%O 1,2
%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 08 2003
%E Edited, corrected and extended by _Klaus Brockhaus_, May 11 2003
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