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A088090 For n > 1, a(n) is the smallest number such that n-th concatenation is prime and the smallest palindrome beginning with (but not equal to) this concatenation is also prime. 0
1, 3, 9, 13, 17, 271, 671, 489, 193, 819, 2219, 5719, 5753, 2391, 20089, 3059, 231, 8259, 16719, 18493, 37967, 16197, 8979, 28153, 11583, 10073, 14169, 57589, 85073, 79053, 121009, 148997, 69921, 42033, 12027, 16437, 20743, 57363, 240183, 88689 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Conjecture: sequence is finite.

LINKS

Table of n, a(n) for n=1..40.

EXAMPLE

11, (13 and 131), (139, 13931), (13913 and 139131931), etc. are all prime.

CROSSREFS

Sequence in context: A243656 A240108 A163595 * A075326 A298870 A095234

Adjacent sequences:  A088087 A088088 A088089 * A088091 A088092 A088093

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Sep 23 2003

EXTENSIONS

More terms from David Wasserman, Jul 15 2005

STATUS

approved

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Last modified April 6 08:27 EDT 2020. Contains 333268 sequences. (Running on oeis4.)