|
%I #28 Jun 03 2013 00:31:26
%S 2,3,5,7,100030001,100050001,100060001,100111001,100131001,100161001,
%T 100404001,100656001,100707001,100767001,100888001,100999001,
%U 101030101,101060101,101141101,101171101,101282101,101292101,101343101,101373101,101414101,101424101,101474101
%N "1-ply" palindromic primes; see Comments.
%C From the Ribenboim book: palindromic primes whose length is not a palindromic prime.
%C a(42046) = 999727999 and a(42047) = 1000008000001. [_Charles R Greathouse IV_, Feb 26 2012]
%D Paulo Ribenboim, The New Book of Prime Number Records, Springer-Verlag New York Inc., 1996, p. 160-161.
%H Alvin Hoover Belt and T. D. Noe, <a href="/A208361/b208361.txt">Table of n, a(n) for n = 1..10000</a> (first 100 terms from Alvin Hoover Belt)
%e 2 is a palindromic prime of 1 digit, but 1 is not prime, therefore 2 is a 1-ply palindromic prime.
%e 100050001 is a palindromic prime of 9 digits, but 9 is composite, therefore 100050001 is a 1-ply palindromic prime.
%t 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 *)
%Y Cf. A109830.
%K nonn,base
%O 1,1
%A _Alvin Hoover Belt_, Feb 25 2012
%E a(5)-a(26) from _Charles R Greathouse IV_, Feb 26 2012
|
