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A090084 Even pseudoprimes to base 11. 14
10, 70, 190, 1330, 8170, 9730, 24130, 28462, 58030, 98458, 143830, 144886, 327370, 856786, 1580230, 1620130, 3536470, 5274970, 6082490, 6376126, 6792710, 8066170, 8610610, 14076910, 17728930, 27275158, 42447406, 52970386, 53497978, 68925130
(list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Robert G. Wilson v, Table of n, a(n) for n = 1..84.
Eric Weisstein's World of Mathematics, Fermat Pseudoprime.
MATHEMATICA
Do[ f=PowerMod[ 11, 2n-1, 2n ]; If[ f==1, Print[ 2n ] ], {n, 2, 800000} ] (* Alexander Adamchuk, May 26 2007 *)
lst = {}; Do[ If[ PowerMod[11, 2n - 1, 2n] == 1, AppendTo[lst, 2n]], {n, 2, 2*10^9}]; lst (* Robert G. Wilson v, Jun 01 2007 *)
Select[Range[4, 68926000, 2], PowerMod[11, #-1, #]==1&] (* Harvey P. Dale, Oct 16 2021 *)
CROSSREFS
Cf. A020139.
Sequence in context: A320228 A130548 A160662 * A025221 A271040 A005567
KEYWORD
nonn
AUTHOR
Labos Elemer, Nov 25 2003
EXTENSIONS
More terms from Alexander Adamchuk, May 26 2007
Further terms from Robert G. Wilson v, Jun 01 2007
STATUS
approved

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Last modified September 18 13:45 EDT 2024. Contains 376000 sequences. (Running on oeis4.)