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A071249 Numbers k such that gcd(k, R(k)) > 1, where R(k) (A004086) is the digit reversal of k. 4

%I #17 Sep 20 2021 09:02:51

%S 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 44,45,46,48,50,51,54,55,57,60,62,63,64,66,68,69,70,72,75,77,78,80,81,

%U 82,84,86,87,88,90,93,96,99,101,102,105,108,110,111,114,117,120,121

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

%C Numbers k such that A055483(k) > 1. - _Reinhard Zumkeller_, Jun 18 2013

%H Reinhard Zumkeller, <a href="/A071249/b071249.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[ Range[125], GCD[ #, FromDigits[ Reverse[ IntegerDigits[ # ]]]] > 1 & ]

%o (Haskell)

%o a071249 n = a071249_list !! (n-1)

%o a071249_list = filter ((> 1) . a055483) [1..]

%o -- _Reinhard Zumkeller_, Jun 18 2013

%Y Cf. A004086, A055483, A226778 (complement).

%K base,nonn

%O 1,1

%A _Amarnath Murthy_, May 21 2002

%E Edited by _Robert G. Wilson v_, Jun 07 2002

%E Definition corrected by _N. J. A. Sloane_, Aug 27 2020 following a suggestion from José Hernández Santiago

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Last modified April 23 02:53 EDT 2024. Contains 371906 sequences. (Running on oeis4.)