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%I #34 Jan 26 2023 11:39:49
%S 271129,78557,1777613,169073869
%N Least k such that k*2^m + 1 has a covering set with precisely n primes.
%C a(10) > 2^31. a(11) = 1143502909. - _Arkadiusz Wesolowski_, Apr 29 2012
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Covering_set">Covering set</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Sierpinski_number">Sierpinski number</a>
%e 271129 has the covering set {3, 5, 7, 13, 17, 241}.
%e 78557 has the covering set {3, 5, 7, 13, 19, 37, 73}.
%e 1777613 has the covering set {3, 5, 7, 13, 17, 19, 109, 433}.
%e 169073869 has the covering set {3, 5, 7, 11, 13, 41, 61, 151, 331}.
%Y Cf. A076336.
%K more,nonn
%O 6,1
%A _Arkadiusz Wesolowski_, Feb 10 2012