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%I #28 Jan 16 2022 14:22:07
%S 10,20,21,30,31,32,40,41,42,43,50,51,52,53,54,60,61,62,63,64,65,70,71,
%T 72,73,74,75,76,80,81,82,83,84,85,86,87,90,91,92,93,94,95,96,97,98,
%U 100,110,120,130,140,150,160,170,180,190,200,201,210,211,220,221,230,231
%N Numbers k such that reversal(k) < k.
%H David A. Corneth, <a href="/A071590/b071590.txt">Table of n, a(n) for n = 1..5400</a> (first 1000 terms from T. D. Noe)
%t Select[Range[300], # > FromDigits[Reverse[IntegerDigits[#]]] &] (* _T. D. Noe_, Mar 14 2012 *)
%t Select[Range[300],IntegerReverse[#]<#&] (* _Harvey P. Dale_, Jan 16 2022 *)
%o (PARI) for(i=2,300,n=(i); s=ceil(log(n)/log(10)); if((sum(i=0,s,10^(s-i-1)*(floor(n/10^i*1.)-10*floor(n/10^(i+1)*1.))))<i,print1((i),",")))
%o (PARI) is(n) = {fromdigits(Vecrev(digits(n)))<n} \\ _David A. Corneth_, Apr 07 2021
%o (Python)
%o def ok(n): return int(str(n)[::-1]) < n
%o print([k for k in range(232) if ok(k)]) # _Michael S. Branicky_, Oct 20 2021
%Y Cf. A004086 (digit reversal), A071589 (reversal(k) > k), A002113 (reversal(k) = k).
%Y Cf. A161602 (binary reversal(k) < k).
%K nonn,easy,base
%O 1,1
%A _Benoit Cloitre_, Jun 01 2002
%E Definition corrected by _Harvey P. Dale_, Jan 16 2022
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