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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
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
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
Sequence in context: A124322 A209037 A334455 * A239694 A097883 A290020
KEYWORD
base,easy,nonn
AUTHOR
Robert G. Wilson v, Sep 09 2002
STATUS
approved