cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A071249 Numbers k such that gcd(k, R(k)) > 1, where R(k) (A004086) is the digit reversal of k.

This page as a plain text file.
%I A071249 #17 Sep 20 2021 09:02:51
%S A071249 2,3,4,5,6,7,8,9,11,12,15,18,20,21,22,24,26,27,28,30,33,36,39,40,42,
%T A071249 44,45,46,48,50,51,54,55,57,60,62,63,64,66,68,69,70,72,75,77,78,80,81,
%U A071249 82,84,86,87,88,90,93,96,99,101,102,105,108,110,111,114,117,120,121
%N A071249 Numbers k such that gcd(k, R(k)) > 1, where R(k) (A004086) is the digit reversal of k.
%C A071249 Numbers k such that A055483(k) > 1. - _Reinhard Zumkeller_, Jun 18 2013
%H A071249 Reinhard Zumkeller, <a href="/A071249/b071249.txt">Table of n, a(n) for n = 1..10000</a>
%t A071249 Select[ Range[125], GCD[ #, FromDigits[ Reverse[ IntegerDigits[ # ]]]] > 1 & ]
%o A071249 (Haskell)
%o A071249 a071249 n = a071249_list !! (n-1)
%o A071249 a071249_list = filter ((> 1) . a055483) [1..]
%o A071249 -- _Reinhard Zumkeller_, Jun 18 2013
%Y A071249 Cf. A004086, A055483, A226778 (complement).
%K A071249 base,nonn
%O A071249 1,1
%A A071249 _Amarnath Murthy_, May 21 2002
%E A071249 Edited by _Robert G. Wilson v_, Jun 07 2002
%E A071249 Definition corrected by _N. J. A. Sloane_, Aug 27 2020 following a suggestion from José Hernández Santiago