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 A155905 Numbers n such that it is possible to append a single digit to the end of 2^n to make it prime. 0
 0, 1, 2, 3, 4, 6, 7, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 24, 25, 27, 30, 31, 33, 36, 38, 42, 43, 46, 49, 50, 51, 54, 55, 57, 58, 60, 64, 65, 73, 74, 84, 93, 106, 108, 123, 126, 129, 139, 150, 162, 183, 187, 196, 198, 220, 271, 273, 279, 301, 312, 379, 392 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Expected to be infinite because the harmonic series diverges. LINKS EXAMPLE For example 641 and 1283 are prime so 6 and 7 are in the sequence respectively. CROSSREFS Sequence in context: A250252 A246274 A057519 * A287531 A047518 A179834 Adjacent sequences:  A155902 A155903 A155904 * A155906 A155907 A155908 KEYWORD nonn,base AUTHOR Dmitry Kamenetsky, Jan 30 2009 STATUS approved

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Last modified December 10 04:15 EST 2019. Contains 329885 sequences. (Running on oeis4.)