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 A050718 Inserting a digit '8' between adjacent decimal digits of n makes a prime. 1
 11, 21, 23, 33, 39, 47, 57, 63, 77, 81, 83, 87, 93, 109, 111, 127, 129, 141, 153, 157, 177, 201, 207, 211, 213, 223, 229, 237, 267, 279, 303, 313, 319, 321, 327, 373, 417, 421, 433, 441, 447, 459, 471, 477, 483, 489, 499, 519, 541, 567, 577, 579, 589, 607 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Arguably 2, 3, 5, and 7 should be in this sequence. - Charles R Greathouse IV, Sep 25 2012 LINKS EXAMPLE E.g. 177 becomes 1(8)7(8)7 which is the prime 18787. CROSSREFS Cf. A050674, A050711-A050719. Sequence in context: A117841 A105956 A178413 * A189226 A195100 A125164 Adjacent sequences:  A050715 A050716 A050717 * A050719 A050720 A050721 KEYWORD nonn,base AUTHOR Patrick De Geest, Aug 15 1999. STATUS approved

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