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 A263392 Riesel numbers that have at least two covering sets. 1
 66837283, 68026001, 71344361, 71604733, 74477159, 94270439, 97579567, 122606647, 140022313, 153196541, 170969579, 182720077, 198885523, 211327993, 220316413, 227116031, 280536071, 285155137, 290419777, 292202437, 293175191, 309240779, 324576431, 331006603 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Wikipedia, Riesel number EXAMPLE For every k >= 1, 97579567*2^k - 1 has a divisor in the set {3, 5, 7, 13, 17, 241} and also in the set {3, 5, 13, 17, 97, 241, 257}. 97579567 is therefore in the sequence. CROSSREFS Cf. A101036, A263391. Sequence in context: A184215 A151697 A138085 * A011576 A089081 A161774 Adjacent sequences:  A263389 A263390 A263391 * A263393 A263394 A263395 KEYWORD nonn AUTHOR Arkadiusz Wesolowski, Oct 16 2015 EXTENSIONS 1 term inserted by Arkadiusz Wesolowski, Aug 28 2016 More terms from Arkadiusz Wesolowski, Jan 09 2018 STATUS approved

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Last modified August 12 05:33 EDT 2020. Contains 336438 sequences. (Running on oeis4.)