A262533 Minimal nested palindromic primes with seed 0000000.

19000000091, 1190000000911, 36119000000091163, 953611900000009116359, 9095361190000000911635909, 790953611900000009116359097, 1479095361190000000911635909741, 72147909536119000000091163590974127, 10572147909536119000000091163590974127501

Offset

2,1

Comments

Let s be a palindrome and put a(1) = s. Let a(2) be the least palindromic prime having s in the middle; for n > 2, let a(n) be the least palindromic prime having a(n-1) in the middle. Then (a(n)) is the sequence of minimal nested palindromic primes with seed s. (For A260444, the seed is not an integer, so that the offset is 2.)

Links

Clark Kimberling, Table of n, a(n) for n = 2..200

Example

As a triangle:
            0000000
          19000000091
         1190000000911
       36119000000091163
     953611900000009116359
   9095361190000000911635909
  790953611900000009116359097

Mathematica

s0 = "0000000"; s = {ToExpression[s0]}; Do[NestWhile[# + 1 &, 1, ! PrimeQ[tmp = FromDigits[Join[#, IntegerDigits[Last[s], 10, Max[StringLength[s0], Length[IntegerDigits[Last[s]]]]], Reverse[#]]&[IntegerDigits[#]]]] &]; AppendTo[s, tmp], {10}]; s0 <> ", " <> StringTake[ToString[Rest[s]], {2, -2}]
(* Peter J. C. Moses, Sep 23 2015 *)

Crossrefs

Cf. A261881.

Sequence in context: A270895 A273186 A185932 * A317288 A234397 A234194

Adjacent sequences: A262530 A262531 A262532 * A262534 A262535 A262536

Keyword

nonn,base,easy

Author

Clark Kimberling, Sep 24 2015

Status

approved