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%I #10 Jun 07 2016 19:18:31
%S 3,2,2,2,10,3,2,18,3,4,2,6,5,6,46,52,4,6,5,7,2,78,5,8,8,10,102,2,5,8,
%T 2,10,136,138,148,3,7,162,166,3,178,10,6,12,6,11,8,222,8,12,3,14,12,8,
%U 2,262,268,7,11,14,282,292,7,310,2,316,15,9,346,8,10,358,366,4,13,10,388
%N Smallest base relative to which the n-th prime is palindromic.
%C Subset of A016026 for primes only.
%H Harvey P. Dale, <a href="/A065437/b065437.txt">Table of n, a(n) for n = 1..1000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PalindromicPrime.html">Palindromic Primes</a>
%e 71 is the 20th prime and can be written as 131 in base 7, hence a(20)=7.
%t PrimeMinBase[ n_ ] := NestWhile[ # + 1 &, 2, IntegerDigits[ Prime[ n ], # ] != Reverse[ IntegerDigits[ Prime[ n ], # ] ] & ]
%t sbr[n_]:=Module[{k=2},While[IntegerDigits[n,k]!=Reverse[ IntegerDigits[ n,k]], k++]; k]; Table[sbr[n],{n,Prime[Range[80]]}] (* _Harvey P. Dale_, Jun 07 2016 *)
%Y Cf. A016026.
%K base,easy,nonn
%O 1,1
%A Peter Bertok (peter(AT)bertok.com), Nov 23 2001
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