A130437 Even pseudoprimes to base 19.

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

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.

Index entries for sequences related to pseudoprimes

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.

Cf. A020147, A006935, A130433, A090082, A090083, A090084, A090085, A130434, A130435, A130436, A130438, A130439, A130440, A130441, A130442, A130443.

Sequence in context: A354019 A052682 A214592 * A119813 A370716 A119986

Adjacent sequences: A130434 A130435 A130436 * A130438 A130439 A130440

Keyword

nonn

Author

Alexander Adamchuk, May 26 2007

Extensions

More terms from Robert G. Wilson v, Jun 01 2007

Status

approved