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A130442 Even pseudoprimes to base 41. 13
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.

Index entries for sequences related to pseudoprimes

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 - from 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. Cf. A090083, A090084, A090085. Cf. A130434, A130435, A130436, A130437, A130438, A130439, A130440, A130441, A130443.

Cf. A020169, A006935, A130433, A090082, A090083, A090084, A090085, A130434, A130435, A130436, A130437, A130438, A130439, A130440, A130441, A130443.

Sequence in context: A032618 A090696 A048247 * A031073 A037004 A136861

Adjacent sequences:  A130439 A130440 A130441 * A130443 A130444 A130445

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 November 22 03:54 EST 2014. Contains 249804 sequences.