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%I #6 Nov 09 2015 16:16:15
%S 1,111,1411141,12141114121,10412141114121401,11610412141114121401611,
%T 171161041214111412140161171,303171161041214111412140161171303,
%U 3230317116104121411141214016117130323,71323031711610412141114121401611713032317
%N Minimal nested palindromic base-8 primes with seed 1; see Comments.
%C Using only base-8 digits 0,1,2,3,4,5,6,7 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 have a(n-1) in the middle. Then (a(n)) is the sequence of minimal nested palindromic base-8 primes with seed s.
%H Clark Kimberling, <a href="/A262661/b262661.txt">Table of n, a(n) for n = 1..300</a>
%e a(3) = 1411141 is the least base-8 prime having a(2) = 111 in its middle. Triangular format:
%e 1
%e 111
%e 1411141
%e 12141114121
%e 10412141114121401
%e 11610412141114121401611
%t s = {1}; base = 8; z = 20; Do[NestWhile[# + 1 &, 1, ! PrimeQ[tmp = FromDigits[Join[#, IntegerDigits[Last[s]], Reverse[#]] &[IntegerDigits[#, base]], base]] &];
%t AppendTo[s, FromDigits[IntegerDigits[tmp, base]]], {z}]; s (* A262661 *)
%t Map[FromDigits[ToString[#], base] &, s] (* A262662 *)
%t (* _Peter J. C. Moses_, Sep 01 2015 *)
%Y Cf. A261881 (base 10), A262662, A262627.
%K nonn,easy,base
%O 1,2
%A _Clark Kimberling_, Oct 31 2015
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