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 A208361 "1-ply" palindromic primes; see Comments. 2
 2, 3, 5, 7, 100030001, 100050001, 100060001, 100111001, 100131001, 100161001, 100404001, 100656001, 100707001, 100767001, 100888001, 100999001, 101030101, 101060101, 101141101, 101171101, 101282101, 101292101, 101343101, 101373101, 101414101, 101424101, 101474101 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS From the Ribenboim book: palindromic primes whose length is not a palindromic prime. a(42046) = 999727999 and a(42047) = 1000008000001. [Charles R Greathouse IV, Feb 26 2012] REFERENCES Paulo Ribenboim, The New Book of Prime Number Records, Springer-Verlag New York Inc., 1996, p. 160-161. LINKS Alvin Hoover Belt and T. D. Noe, Table of n, a(n) for n = 1..10000 (first 100 terms from Alvin Hoover Belt) EXAMPLE 2 is a palindromic prime of 1 digit, but 1 is not prime, therefore 2 is a 1-ply palindromic prime. 100050001 is a palindromic prime of 9 digits, but 9 is composite, therefore 100050001 is a 1-ply palindromic prime. MATHEMATICA t = {2, 3, 5, 7}; n = 10000; While[n <= 99999 && Length[t] < 100, n = n + 1; d = IntegerDigits[n]; d2 = FromDigits[Join[d, Rest[Reverse[d]]]]; If[PrimeQ[d2], AppendTo[t, d2]]]; t (* T. D. Noe, Jun 03 2013 *) CROSSREFS Cf. A109830. Sequence in context: A037948 A007659 A288715 * A145380 A136740 A105994 Adjacent sequences:  A208358 A208359 A208360 * A208362 A208363 A208364 KEYWORD nonn,base AUTHOR Alvin Hoover Belt, Feb 25 2012 EXTENSIONS a(5)-a(26) from Charles R Greathouse IV, Feb 26 2012 STATUS approved

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Last modified May 10 05:05 EDT 2021. Contains 343748 sequences. (Running on oeis4.)