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 A032696 Exactly 6 digits from {1,2,3,4,5,6,7,8,9} can precede a(n) to form a prime. 0
 3, 57, 297, 2189, 25697, 76721, 123747, 124443, 132653, 218207, 244099, 261023, 267787, 297059, 304389, 346623, 366989, 411971, 462751, 551057, 596897, 643181, 647193, 665967, 671573, 688143, 701207, 742197, 748563, 867003, 872313, 877331 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Finding 7, 8 and 9 preceding digits is a difficult job! LINKS EXAMPLE If a(n) = 57 then we find '1'57, '2'57, '4'57, '5'57, '7'57 and '8'57 to be primes. CROSSREFS Sequence in context: A051227 A122548 A078728 * A337790 A131466 A171356 Adjacent sequences:  A032693 A032694 A032695 * A032697 A032698 A032699 KEYWORD nonn,base AUTHOR Patrick De Geest, May 15 1998 STATUS approved

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Last modified December 6 19:30 EST 2021. Contains 349567 sequences. (Running on oeis4.)