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 A258074 Table read by rows: each row represents the constant and exponent of a Colbert number. 0
 5359, 5054502, 33661, 7031232, 28433, 7830457, 27653, 9167433, 19249, 13018586, 10223, 31172165 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Each row has two entries [k,n]. With this notation, the corresponding Colbert number is k*2^n+1. A Colbert number is an integer with more than 1,000,000 digits that is prime and has contributed to the in-progress computational proof that 78557 is the smallest Sierpiński number (A076336). The last number, corresponding to [10223,31172165], is currently the largest known prime that is not a Mersenne prime. This table can only have (and is expected to have) five more rows corresponding to constants k equal to 21181, 22699, 24737, 55459, and 67607. LINKS C. K. Caldwell, The Prime Glossary, Colbert Number C. K. Caldwell, The Prime Database, 10223*2^31172165+1 W. Sierpiński, Sur un problème concernant les nombres k * 2^n + 1, Elem. Math., 15 (1960), pp. 73-74. Wikipedia, Seventeen or Bust EXAMPLE The table is as follows: 5359, 5054502; 33661, 7031232; 28433, 7830457; 27653, 9167433; 19249, 13018586 10223, 31172165 CROSSREFS Cf. A076336, A064699, A064721. Sequence in context: A206681 A203962 A145770 * A237295 A296146 A063408 Adjacent sequences:  A258071 A258072 A258073 * A258075 A258076 A258077 KEYWORD nonn,tabf,fini,more AUTHOR Tom Edgar, May 18 2015 EXTENSIONS a(11)-a(12) from Richard N. Smith, Jul 15 2019, following by the prime 10223*2^31172165+1 found by PrimeGrid. STATUS approved

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Last modified May 29 10:41 EDT 2020. Contains 334699 sequences. (Running on oeis4.)