1,1

Digits are in ascending order beginning with 9 and after 9 comes 0.

The sequence "Primes with n consecutive digits descending beginning with the digit nine" has no terms.

There is no further term up to 26000. - Farideh Firoozbakht, Sep 11 2006

Table of n, a(n) for n=1..3.

13 is a term since 9012345678901 is a prime.

fQ[n_] := PrimeQ@ FromDigits@ Mod[8+Range@n, 10]; lst = {}; Do[ If[fQ@n, AppendTo[lst, n]; Print@n], {n, 5000}]; lst

Flatten[Position[Table[FromDigits[PadRight[{}, n, {9, 0, 1, 2, 3, 4, 5, 6, 7, 8}]], {n, 100}], _?PrimeQ]] (* Harvey P. Dale, Sep 06 2015 *)

Cf. A006055, A120819, A120820, A120821, A120822, A120823, A120824, A120825, A120826.

Sequence in context: A045472 A240950 A141293 * A320631 A309356 A322551

Adjacent sequences: A120824 A120825 A120826 * A120828 A120829 A120830

base,bref,hard,nonn

Robert G. Wilson v, Jul 05 2006

approved