login
A099630
Smallest and largest primes pairwise displayed with k digits from k=2,3,... with repeated decimal digits.
0
11, 11, 101, 997, 1009, 9973, 10007, 99991, 100003, 999983, 1000003, 9999991, 10000019, 99999989, 100000007, 999999937, 1000000007, 9999999967, 10000000019, 99999999977, 100000000003, 999999999989, 1000000000039, 9999999999971, 10000000000037, 99999999999973
OFFSET
1,1
COMMENTS
Contrary to A099629, this sequence is evidently infinite. Essentially [for more than 2 digits] consists of pairs of {nextprime[10^j],prevprime[10^(j+1)]}.
MATHEMATICA
Join[{11, 11}, Flatten[Table[{NextPrime[10^n], NextPrime[10^(n+1), -1]}, {n, 2, 20}]]] (* Harvey P. Dale, Jun 04 2018 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Labos Elemer, Oct 26 2004
EXTENSIONS
Corrected and extended by Harvey P. Dale, Jun 04 2018
STATUS
approved