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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). 22
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

REFERENCES

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

LINKS

Table of n, a(n) for n=0..59.

Patrick De Geest, PDP's Sorted By Length

CROSSREFS

Cf. A082697-A082719, A077797, A077799.

Sequence in context: A033039 A322660 A161957 * A033037 A246413 A246411

Adjacent sequences:  A082717 A082718 A082719 * A082721 A082722 A082723

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Apr 13 2003

STATUS

approved

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Last modified December 12 20:12 EST 2019. Contains 329961 sequences. (Running on oeis4.)