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A071606
Smallest zero-free palindromic prime of 2n + 1 digits.
1
2, 131, 11311, 1114111, 111181111, 11112721111, 1111118111111, 111111151111111, 11111112521111111, 1111111111111111111, 111111111161111111111, 11111111111111111111111, 1111111111129211111111111, 111111111111212111111111111, 11111111111111611111111111111
OFFSET
0,1
LINKS
MATHEMATICA
a[n_] := Block[{k = (10^(n + 1) - 1)/9}, While[m = FromDigits[ Join[ IntegerDigits[k], Reverse[ Drop[ IntegerDigits[k], -1]]]]; !PrimeQ[m], k++ ]; m]; Table[ a[n], {n, 0, 13}]
CROSSREFS
Cf. A028989.
Sequence in context: A125633 A089662 A119778 * A080282 A131931 A020524
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, Jun 21 2002
EXTENSIONS
Edited by Robert G. Wilson v, Jun 21 2002
More terms from Sean A. Irvine, Jul 28 2024
STATUS
approved