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Numbers m, such that the smallest prime factor of 1+78557*2^m doesn't belong to the covering set {3, 5, 7, 13, 19, 37, 73}.
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%I #4 May 19 2015 19:01:20

%S 39,183,219,1047,1227,1299,1875,2271,2559,2703,3315,3531,3819,4359,

%T 5079,5187,5403,6015,6339,6447,6843,7491,7599,7671,8499,8535,8859,

%U 9327,9579,10119,10155,10623,10983,11379,11667,11811,12639,12711,13467,13755,13899

%N Numbers m, such that the smallest prime factor of 1+78557*2^m doesn't belong to the covering set {3, 5, 7, 13, 19, 37, 73}.

%C A258091(a(n)) < 73, as each term in A258073 has at least one prime factor in the covering set.

%H Reinhard Zumkeller, <a href="/A258095/b258095.txt">Table of n, a(n) for n = 1..250</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Sierpinski_number">Sierpinski Number</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Covering_set">Covering set</a>

%e a(1) = 39; A258073(39) = 43187167471599617 = 71 * 73 * 211 * 39490356709, and 71 is not an element of the covering set.

%o (Haskell)

%o a258095 n = a258095_list !! (n-1)

%o a258095_list = filter

%o (\x -> a258091 x `notElem` [3, 5, 7, 13, 19, 37, 73]) [1..]

%Y Cf. A258073, A258091, A020639.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, May 19 2015