A120826 a(n) consecutive digits ascending beginning with the digit 8 give a prime.

2, 82, 152, 7066, 84892

Offset

1,1

Comments

Digits are in ascending order beginning with 8 and after 9 comes 0.

The sequence "a(n) consecutive digits descending beginning with the digit 8 give a prime" has no terms.

a(6) > 10^5. - Michael S. Branicky, Apr 11 2025

Links

Table of n, a(n) for n=1..5.

Example

2 is a term since 89 is a prime.
82 is a term because 8901234567890123456789012345678901234567890123456789012345678901234567890123456789 is a prime.

Mathematica

fQ[n_] := PrimeQ@ FromDigits@ Mod[7+Range@n, 10]; lst = {}; Do[ If[fQ@n, AppendTo[lst, n]; Print@n], {n, 5000}]; lst

Crossrefs

Cf. A006055, A120819, A120820, A120821, A120822, A120823, A120824, A120825, A120827.

Sequence in context: A090603 A020955 A230398 * A343588 A259308 A202965

Adjacent sequences: A120823 A120824 A120825 * A120827 A120828 A120829

Keyword

nonn,base,hard,more

Author

Robert G. Wilson v, Jul 05 2006

Extensions

a(4) from Bert Dobbelaere, Apr 01 2025

a(5) from Michael S. Branicky, Apr 03 2025

Status

approved