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A096497
Prime following n-th repunit.
18
2, 13, 113, 1117, 11113, 111119, 1111151, 11111117, 111111113, 1111111121, 11111111113, 111111111149, 1111111111139, 11111111111123, 111111111111229, 1111111111111123, 11111111111111119, 111111111111111131, 1111111111111111171, 11111111111111111131, 111111111111111111157, 1111111111111111111189
OFFSET
1,1
COMMENTS
Not equal to A068693: first and 2nd terms differ.
FORMULA
a(n) = A002275(n) + A096869(n) = A096498(n) + A096499(n).
MATHEMATICA
Table[NextPrime[(10^n-1)/9], {n, 40}]
Table[NextPrime[FromDigits[PadRight[{}, n, 1]]], {n, 30}] (* Harvey P. Dale, Aug 11 2023 *)
PROG
(PARI) a(n) = nextprime((10^n-1)/9 + 1); \\ Michel Marcus, May 02 2016
(Python)
from sympy import nextprime
def A096497(n):
return nextprime((10**n-1)//9) # Chai Wah Wu, Nov 04 2019
CROSSREFS
Sequence in context: A046811 A046813 A208316 * A247153 A088604 A127891
KEYWORD
nonn
AUTHOR
Labos Elemer, Jul 09 2004
STATUS
approved