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A075241 Least base for which the n-th prime has no prime reversal in that base. 4

%I

%S 2,3,5,7,4,6,3,2,6,3,7,4,4,3,4,5,2,7,10,3,3,2,6,2,3,6,2,3,2,4,4,4,2,2,

%T 2,4,2,4,4,4,2,4,2,10,3,3,2,3,4,3,9,2,2,3,3,4,3,2,3,2,3,2,3,2,3,2,4,3,

%U 2,4,6,4,2,3,2,3,2,2,2,5,2,4,4,3,2,3,6,2,3,4,2,3,3,6,2,4,3,4,2,2,2,2,2

%N Least base for which the n-th prime has no prime reversal in that base.

%C a(n) is always less than or equal to n-th prime and once past a(6) it is always less than n.

%H Amiram Eldar, <a href="/A075241/b075241.txt">Table of n, a(n) for n = 1..10000</a>

%t a = {}; Do[k = 2; p = Prime[n]; While[ PrimeQ[ FromDigits[ Reverse[ IntegerDigits[p, k]], k]], k++ ]; a = Append[a, k], {n, 1, 105}]; a

%Y Cf. A075240, A075242.

%K base,easy,nonn

%O 1,1

%A _Robert G. Wilson v_, Sep 09 2002

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Last modified September 23 12:20 EDT 2021. Contains 347617 sequences. (Running on oeis4.)