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A062215
Numbers k such that the smoothly undulating palindromic number (19*10^k - 91)/99 is a prime.
0
3, 33, 133, 1969, 2335
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=33 -> (19*10^33 - 91)/99 = 191919191919191919191919191919191.
CROSSREFS
KEYWORD
nonn,base
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