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A082705
Numbers k such that (29*10^(k-1) + 7)/9 is a depression prime.
1
7, 9, 895, 1525, 3037, 21157
OFFSET
1,1
COMMENTS
Prime versus probable prime status and proofs are given in the author's table.
REFERENCES
C. Caldwell and H. Dubner, "Journal of Recreational Mathematics", Volume 28, No. 1, 1996-97, pp. 1-9.
FORMULA
a(n) = A056252(n) + 2.
EXAMPLE
k=9 -> (29*10^(9-1) + 7)/9 = 322222223.
CROSSREFS
KEYWORD
nonn,base,hard,more
AUTHOR
Patrick De Geest, Apr 13 2003
EXTENSIONS
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
Edited by Ray Chandler, Nov 05 2014
STATUS
approved