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 A074814 Numbers k such that the number of primes between k and 2k (inclusive) is equal to the number of primes between k and reverse(k) (inclusive). 0
 10, 25, 37, 40, 81, 102, 120, 204, 295, 340, 350, 387, 397, 1620, 1743, 2995, 3627, 3997, 4450, 4629, 4999, 8090, 8490, 9201, 9301, 10002, 12310, 17043, 20004, 22954, 29995, 30006, 36027, 39997, 40008, 40240, 42540, 42958, 46029, 49999, 55550, 60360, 65460, 82180, 85480, 200004 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE 10 is included since there are four primes between 10 and 1 and four primes between 10 and 20. PROG (PARI) ok(n)={my(r=fromdigits(Vecrev(digits(n)))); if(r>n, primepi(2*n) == primepi(r), primepi(n) - primepi(r-1) == primepi(2*n) - primepi(n-1))} { for(n=1, 10^5, if(ok(n), print1(n, ", "))) } \\ Andrew Howroyd, Feb 12 2020 CROSSREFS Sequence in context: A274046 A014090 A154057 * A002600 A087473 A014120 Adjacent sequences:  A074811 A074812 A074813 * A074815 A074816 A074817 KEYWORD base,nonn AUTHOR Jason Earls, Sep 08 2002 EXTENSIONS More terms from Sascha Kurz, Feb 10 2003 Terms a(28) and beyond from Andrew Howroyd, Feb 12 2020 STATUS approved

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Last modified October 27 01:02 EDT 2020. Contains 338035 sequences. (Running on oeis4.)