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A158997 Palindromes of the form m*reversal(m)+1 where m >= reversal(m), sorted on m. 2

%I

%S 2,5,11,404,737,161,575,101,1001,10001,1008001,1008001,100001,

%T 227218812722,1000001,10000001,3536651551566353,100000001,1000000001,

%U 26993605822850639962,10000000001,100000000001,140452633741147336254041,1000000000001

%N Palindromes of the form m*reversal(m)+1 where m >= reversal(m), sorted on m.

%H Carlos Rivera,<a href="http://www.primepuzzles.net/puzzles/puzz_496.htm">P*R(P)+1 = Palprime</a>

%t r[n_]:=FromDigits[Reverse[IntegerDigits[n]]];Do[If[m>=r[m]&& r[m r[m]+1]==m r[m]+1,Print[m r[m]+1]],{m,1000000000}]

%Y Cf. A177856, A158999.

%K nonn,base,more

%O 1,1

%A _Farideh Firoozbakht_, Jul 09 2009

%E a(20)-a(22) from _Sean A. Irvine_, Dec 13 2009

%E Cross-reference fixed by _Franklin T. Adams-Watters_, May 14 2010

%E a(23)-a(24) from _Giovanni Resta_, Aug 30 2018

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Last modified April 19 15:45 EDT 2021. Contains 343116 sequences. (Running on oeis4.)