A139686 Odd multiplicative orders of 2 modulo primes.

3, 11, 5, 23, 35, 9, 39, 11, 51, 7, 15, 83, 95, 99, 37, 29, 119, 131, 135, 155, 21, 179, 183, 191, 43, 73, 231, 239, 243, 251, 299, 25, 303, 45, 323, 359, 121, 371, 375, 411, 419, 431, 55, 443, 91, 153, 117, 483, 491, 495, 515, 519, 531, 543, 29, 575, 611, 615, 639

Offset: 1

Author

Max Alekseyev, Apr 29 2008

Keywords

• nonn

Comments

Subsequence of A014664, consisting of odd elements.

Links

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

Crossrefs

Cf. A014664, A014663 (corresponding primes).

Cf. other bases: this sequence (base 2), A385226 (base 3), A385227 (base 4), A385193 (base 5), A385228 (base -2), A385229 (base -3), A385230 (base -4), A385231 (base -5).

Programs

Mathematica

p = Select[Range[1000], PrimeQ]; Select[MultiplicativeOrder[2, #] & /@ p, OddQ] (* Amiram Eldar, Jul 30 2020 *)

PARI

forprime(p=3,10^5,z=znorder(Mod(2,p));if(z%2,print1(z,", ")))

Formula

a(n) = multiplicative order of 2 modulo A014663(n).