A099630 Smallest and largest primes pairwise displayed with k digits from k=2,3,... with repeated decimal digits.

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)]}.

Links

Table of n, a(n) for n=1..26.

Mathematica

Join[{11, 11}, Flatten[Table[{NextPrime[10^n], NextPrime[10^(n+1), -1]}, {n, 2, 20}]]] (* Harvey P. Dale, Jun 04 2018 *)

Crossrefs

Cf. A098224-A098227.

Sequence in context: A290206 A288981 A289766 * A088772 A088771 A088773

Adjacent sequences: A099627 A099628 A099629 * A099631 A099632 A099633

Keyword

base,nonn

Author

Labos Elemer, Oct 26 2004

Extensions

Corrected and extended by Harvey P. Dale, Jun 04 2018

Status

approved