A262533 - OEIS

%I #9 Oct 02 2015 13:09:37

%S 19000000091,1190000000911,36119000000091163,953611900000009116359,

%T 9095361190000000911635909,790953611900000009116359097,

%U 1479095361190000000911635909741,72147909536119000000091163590974127,10572147909536119000000091163590974127501

%N Minimal nested palindromic primes with seed 0000000.

%C 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.)

%H Clark Kimberling, <a href="/A262533/b262533.txt">Table of n, a(n) for n = 2..200</a>

%e As a triangle:

%e             0000000

%e           19000000091

%e          1190000000911

%e        36119000000091163

%e      953611900000009116359

%e    9095361190000000911635909

%e   790953611900000009116359097

%t 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}]

%t (* _Peter J. C. Moses_, Sep 23 2015 *)

%Y Cf. A261881.

%K nonn,base,easy

%O 2,1

%A _Clark Kimberling_, Sep 24 2015