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A099083
Numbers k such that 1.2. ... .k-1.k - 2 is prime (where dot between numbers means concatenation).
3
5, 31, 103, 111, 119, 201
(list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Each term is odd and next term is greater than 2200.
Any further terms exceed 13000. - Lucas A. Brown, Mar 06 2024
Any further terms exceed 30000. - Michael S. Branicky, Sep 13 2024
LINKS
Table of n, a(n) for n=1..6.
EXAMPLE
31 is in the sequence because 12345678910111213141516171819202122232425262728293031 - 2 is prime.
CROSSREFS
Cf. A099081, A099082.
Sequence in context: A362304 A024399 A183520 * A212523 A096944 A053699
Adjacent sequences: A099080 A099081 A099082 * A099084 A099085 A099086
KEYWORD
base,more,nonn
AUTHOR
Farideh Firoozbakht, Nov 03 2004
STATUS
approved

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Last modified October 4 19:29 EDT 2024. Contains 376520 sequences.
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