A082720 Digit lengths for which there exist plateau or depression primes of the general form a*(10^m-1)/9 +- b*(10^(m-1)+1).

3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 29, 31, 33, 37, 41, 49, 53, 55, 59, 61, 65, 67, 69, 73, 75, 83, 85, 87, 93, 95, 97, 101, 103, 105, 111, 113, 115, 117, 121, 127, 129, 141, 157, 161, 171, 193, 201, 205, 209, 231, 247, 291, 323, 343, 351, 353, 361, 367, 401

Offset: 0

Author

Patrick De Geest, Apr 13 2003

Keywords

• nonn
• base

References

• C. Caldwell and H. Dubner, "Journal of Recreational Mathematics", Volume 28, No. 1, 1996-97, pp. 1-9.

Links

• Patrick De Geest, PDP's Sorted By Length

Crossrefs

Cf. A082697-A082719, A077797, A077799.