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.

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

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: A363406 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