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A206001
Least k such that k*2^m + 1 has a covering set with precisely n primes.
1
271129, 78557, 1777613, 169073869
OFFSET
6,1
COMMENTS
a(10) > 2^31. a(11) = 1143502909. - Arkadiusz Wesolowski, Apr 29 2012
EXAMPLE
271129 has the covering set {3, 5, 7, 13, 17, 241}.
78557 has the covering set {3, 5, 7, 13, 19, 37, 73}.
1777613 has the covering set {3, 5, 7, 13, 17, 19, 109, 433}.
169073869 has the covering set {3, 5, 7, 11, 13, 41, 61, 151, 331}.
CROSSREFS
Cf. A076336.
Sequence in context: A249254 A075467 A257647 * A244561 A137715 A258893
KEYWORD
more,nonn
AUTHOR
STATUS
approved