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A062220 Numbers k such that the smoothly undulating palindromic number (38*10^k - 83)/99 is a prime. 1
3, 9, 15, 17, 21, 57, 4233, 4335, 13221, 26447, 29897, 91997 (list; graph; refs; listen; history; text; internal format)
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
LINKS
EXAMPLE
k=21 -> (38*10^21 - 83)/99 = 383838383838383838383.
CROSSREFS
Sequence in context: A061966 A085328 A291347 * A310328 A043381 A100331
KEYWORD
nonn,base
AUTHOR
Patrick De Geest and Hans Rosenthal (Hans.Rosenthal(AT)t-online.de), Jun 15 2001
EXTENSIONS
a(12)=91997 from Ray Chandler, Jul 29 2011
Edited by Ray Chandler, Aug 17 2011
STATUS
approved

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Last modified April 23 05:20 EDT 2024. Contains 371906 sequences. (Running on oeis4.)