A333743 Odd numbers k such that the multiplicative orders of 2 modulo k and modulo k+2 are equal.

109, 157, 307, 427, 499, 811, 1015, 1183, 1459, 2013, 2251, 2715, 3181, 3259, 3439, 3541, 3889, 3963, 4303, 4339, 4553, 4909, 5197, 6421, 6661, 6997, 8389, 8707, 8779, 9067, 9109, 9663, 10531, 10597, 11731, 12243, 12259, 13009, 13789, 14347, 14437, 14583, 16143

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Multiplicative Order.

Wikipedia, Multiplicative order.

Example

109 is a term since the multiplicative orders of 2 modulo 109 and modulo 111 are both equal to 36.

Mathematica

Select[Range[1, 10^4, 2], MultiplicativeOrder[2, #] ==  MultiplicativeOrder[2, # + 2] &]

Crossrefs

Cf. A002326, A333741, A333744.

Sequence in context: A182451 A161483 A283792 * A141948 A102908 A141998

Adjacent sequences: A333740 A333741 A333742 * A333744 A333745 A333746

Keyword

nonn

Author

Amiram Eldar, Apr 03 2020

Status

approved