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A261455
Numbers n such that 1+131*10^(n-1)+100^n is prime.
0
2, 4, 13, 30, 73, 82, 120, 168, 227, 422, 433, 451, 607, 612, 798, 1527, 6958
OFFSET
1,1
COMMENTS
No other terms < 10000.
EXAMPLE
For n=2, 11311 is prime.
For n=3, 1013101 is not prime.
For n=4, 100131001 is prime.
PROG
(PARI) isok(n)=isprime(1+131*10^(n-1)+100^n) \\ Anders Hellström, Aug 20 2015
CROSSREFS
Sequence in context: A153933 A128601 A034500 * A077325 A148213 A148214
KEYWORD
nonn,more
AUTHOR
Chai Wah Wu, Aug 20 2015
STATUS
approved