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 A179443 Numbers m such that m and 10*m + 1 are both composites. 2
 8, 9, 12, 14, 16, 20, 22, 26, 30, 32, 34, 35, 36, 38, 39, 44, 45, 48, 50, 51, 55, 56, 58, 62, 65, 68, 72, 74, 77, 78, 80, 84, 85, 86, 87, 90, 92, 93, 95, 96, 98, 100, 104, 108, 110, 111, 112, 114, 116, 119, 121, 122, 124, 125, 126, 128, 133, 134, 135, 140, 141 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Corresponding values of 10*m + 1 are in A179444. LINKS Andrew Howroyd, Table of n, a(n) for n = 1..1000 PROG (PARI) is(n)={n>1 && !isprime(n) && !isprime(10*n+1)} select(is, [1..200]) \\ Andrew Howroyd, Jan 04 2020 CROSSREFS Cf. A179444. Sequence in context: A168415 A199635 A131864 * A264828 A080756 A304661 Adjacent sequences:  A179440 A179441 A179442 * A179444 A179445 A179446 KEYWORD nonn AUTHOR Jaroslav Krizek, Jul 14 2010 EXTENSIONS Terms a(43) and beyond from Andrew Howroyd, Jan 04 2020 STATUS approved

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Last modified June 25 08:27 EDT 2021. Contains 345453 sequences. (Running on oeis4.)