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%I #11 Oct 02 2015 13:06:52
%S 11111,121111121,71211111217,3712111112173,98371211111217389,
%T 129837121111121738921,3312983712111112173892133,
%U 1063312983712111112173892133601,12106331298371211111217389213360121,781210633129837121111121738921336012187
%N Minimal nested palindromic primes with seed 11111.
%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.
%H Clark Kimberling, <a href="/A262497/b262497.txt">Table of n, a(n) for n = 1..200</a>
%e As a triangle:
%e 11111
%e 121111121
%e 71211111217
%e 3712111112173
%e 98371211111217389
%e 129837121111121738921
%e 3312983712111112173892133
%e 1063312983712111112173892133601
%t s0 = "11111"; 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 1,1
%A _Clark Kimberling_, Sep 24 2015
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