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A062225
Numbers k such that the smoothly undulating palindromic number (78*10^k - 87)/99 is a prime.
0
3, 5, 21, 27, 95, 2075, 2165, 3047, 3503, 16791, 34883
OFFSET
1,1
COMMENTS
Prime versus probable prime status and proofs are given in the author's table.
No further terms < 100000. - Ray Chandler, Aug 17 2011
EXAMPLE
k=21 -> (78*10^21 - 87)/99 = 787878787878787878787.
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
Patrick De Geest and Hans Rosenthal (Hans.Rosenthal(AT)t-online.de), Jun 15 2001
EXTENSIONS
Edited by Ray Chandler, Aug 17 2011
STATUS
approved