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A130437 Even pseudoprimes to base 19. 13
6, 18, 906, 5466, 257302, 825366, 1880082, 6637546, 6765826, 8936722, 9483706, 34087054, 51914026, 54806454, 57663334, 57819882, 67372378, 91835206, 98963734, 102985926, 117697186, 134457346, 143888806, 172530646, 206623266 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Robert G. Wilson v, Table of n, a(n) for n = 1..51.
Eric Weisstein's World of Mathematics, Fermat Pseudoprime.
MATHEMATICA
lst = {}; Do[ If[ PowerMod[19, 2n - 1, 2n] == 1, AppendTo[lst, 2n]], {n, 2, 2*10^9}]; lst (* Robert G. Wilson v, Jun 01 2007 *)
CROSSREFS
Cf. A020147 = Pseudoprimes to base 19. 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, A130438, A130439, A130440, A130441, A130442, A130443.
Sequence in context: A052682 A214592 A372522 * A119813 A370716 A119986
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 June 9 03:53 EDT 2024. Contains 373227 sequences. (Running on oeis4.)