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 A215477 Semiprimes with consecutive (ascending) digits. 2
 4, 6, 9, 34, 123, 789, 901, 1234, 34567, 56789, 901234, 1234567, 7890123, 567890123, 12345678901, 345678901234567, 4567890123456789, 12345678901234567, 890123456789012345, 3456789012345678901, 456789012345678901234, 123456789012345678901234567, 1234567890123456789012345678901, 23456789012345678901234567890123 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This is to semiprimes A001358 as A006055 is to primes A000040. LINKS EXAMPLE a(9) = 34567 because it is semiprime 13 * 2659, and (3,4,5,6,7) are consecutive ascending digits. CROSSREFS Cf. A001358, A118697, A059043, A006055, A161760. Sequence in context: A338378 A081614 A192220 * A292154 A291717 A303699 Adjacent sequences:  A215474 A215475 A215476 * A215478 A215479 A215480 KEYWORD nonn,base,easy AUTHOR Jonathan Vos Post, Aug 12 2012 EXTENSIONS Corrected and extended by R. J. Mathar, Aug 13 2012 STATUS approved

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Last modified November 30 03:48 EST 2021. Contains 349417 sequences. (Running on oeis4.)