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Search: id:A109028
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%I A109028
%S A109028 16560,25515,27864,42480,46872,51552,57348,61488,65448,67797,69408,
%T A109028 69840,79776,80496,84375,84456,88416,105336,119448,125928,160416,167076,
%U A109028 202032,204984,206928,210960,211104,211464,213750,213792,213920,213984
%N A109028 8-almost primes (A046310) whose digit reversal is different and also 
               has 8 prime factors (with multiplicity). "Emirp Tsolma-8.".
%C A109028 This sequence is the k = 8 instance of the series which begins with k 
               = 1 (emirps), k = 2 (emirpimes), k = 3 (emirp tsolma-3 = A109023), 
               k = 4 (emirp tsolma-4 = A109024), k = 5 (emirp tsolma-5 = A109025), 
               k = 6 (emirp tsolma-6 = A109026), k = 7 (emirp tsolma-7 = A109027).
%C A109028 The Mathematica code for this was written by Ray Chandler who extended 
               this sequence. He also has more values.
%D A109028 Jonathan Vos Post, "1066 and All That: Emirp Tsolma-3 and Related Integer 
               Sequences." Forthcoming paper on this sequence.
%H A109028 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               AlmostPrime.html">Almost Prime</a>.
%H A109028 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               Emirp.html">Emirp</a>.
%H A109028 Eric Weisstein and Jonathan Vos Post, <a href="http://mathworld.wolfram.com/
               Emirpimes.html">Emirpimes.</a>
%e A109028 a(2) = 25515 is in this sequence because 25515 = 3^6 * 5 * 7 is an 8-almost 
               prime and reverse(25515) = 51552 = 2^5 * 3^2 * 179 is also an 8-almost 
               prime.
%Y A109028 Cf. A046310, A006567, A097393, A109018, A109023-A109027, A109029-A109131.
%Y A109028 Sequence in context: A057680 A157796 A091089 this_sequence A057329 A108843 
               A128383
%Y A109028 Adjacent sequences: A109025 A109026 A109027 this_sequence A109029 A109030 
               A109031
%K A109028 nonn,base
%O A109028 1,1
%A A109028 Jonathan Vos Post (jvospost3(AT)gmail.com), Jun 16 2005

    
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Last modified December 10 12:37 EST 2009. Contains 170569 sequences.


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