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A075241 Least base for which the n-th prime has no prime reversal in that base. 4
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, 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, 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MATHEMATICA

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

CROSSREFS

Cf. A075240, A075242.

Sequence in context: A124322 A209037 A334455 * A239694 A097883 A290020

Adjacent sequences:  A075238 A075239 A075240 * A075242 A075243 A075244

KEYWORD

base,easy,nonn

AUTHOR

Robert G. Wilson v, Sep 09 2002

STATUS

approved

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Last modified August 1 13:01 EDT 2021. Contains 346391 sequences. (Running on oeis4.)