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A130442 Even pseudoprimes to base 41. 14
4, 8, 10, 20, 40, 344, 4870, 6892, 17230, 68920, 250820, 296440, 317032, 368722, 369370, 451426, 472312, 473240, 632270, 2326472, 3186730, 3429190, 4438760, 4670956, 4948456, 5509540, 8990356, 11817604, 11841436, 13094342, 17668360 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Robert G. Wilson v, Table of n, a(n) for n = 1..146.
Eric Weisstein's World of Mathematics, Fermat Pseudoprime.
MATHEMATICA
Do[ f=PowerMod[ 41, 2n-1, 2n ]; If[ f==1, Print[ 2n ] ], {n, 2, 500000} ]
lst = {}; Do[ If[ PowerMod[41, 2n - 1, 2n] == 1, AppendTo[lst, 2n]], {n, 2, 2^31}]; lst (* Robert G. Wilson v, Jun 01 2007 *)
CROSSREFS
Cf. A020169 = Pseudoprimes to base 41.
Cf. A006935 = Even pseudoprimes (or primes) to base 2: n divides 2^n - 2, n even.
Cf. A130433 = Even pseudoprimes to base 3.
Cf. A090082 = Even pseudoprimes to base 5.
Sequence in context: A048247 A276607 A338312 * A031073 A323151 A037004
KEYWORD
nonn
AUTHOR
Alexander Adamchuk, May 26 2007
EXTENSIONS
More terms from Robert G. Wilson v, Jun 01 2007
STATUS
approved

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Last modified April 19 16:52 EDT 2024. Contains 371794 sequences. (Running on oeis4.)