Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #16 Nov 04 2024 16:58:31
%S 0,1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,17,18,19,22,23,24,25,26,27,28,
%T 29,33,34,35,36,37,38,39,44,45,46,47,48,49,55,56,57,58,59,66,67,68,69,
%U 77,78,79,88,89,99,101,102,103,104,105,106,107,108,109,111,112,113,114,115
%N List of numbers n whose reverse, R(n), is not less than n.
%C First terms not in A009993 are 11, 22, 33, etc.
%H David A. Corneth, <a href="/A131058/b131058.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[0, 200], FromDigits[Reverse[IntegerDigits[ # ]]]>=#&]
%t Select[Range[0,200],IntegerReverse[#]>=#&]
%o (PARI) is(n) = my(d=digits(n));sum(i=1,#d,10^(#d-i)*d[i]) <= sum(i=1,#d,10^(i-1)*d[i]) \\ _David A. Corneth_, Apr 25 2016
%o (PARI) isok(n) = subst(Polrev(digits(n)), x, 10) >= n; \\ _Michel Marcus_, Apr 25 2016
%Y Cf. A002113, A009993.
%K nonn,base
%O 1,3
%A _Zak Seidov_, Sep 24 2007