A350084 a(n) = ord(2,A006935(n)/2), where ord(k,m) is the multiplicative order of k modulo m.

1, 261, 165, 275, 13425, 1485, 1305, 32085, 825, 3465, 2093, 3135, 495, 495, 261, 847, 9405, 552189, 198561, 261, 579261, 2475, 6237, 166725, 111111, 3393, 3565, 25245, 18585, 4437, 891891, 309455, 37125, 4833, 2301585, 14355, 11781, 3315, 915, 84975, 35259

Offset

1,2

Comments

List of ord(2,k) where k ranges over the odd numbers such that 2^(2*k-1) == 1 (mod k).

Links

Amiram Eldar, Table of n, a(n) for n = 1..1319

Formula

a(n) = ord(2,A347906(n)) = (A006935(n) - 1) / A350083(n).

Example

A006935(2) = 161038, so a(2) = ord(2,161038/2) = 261.
A006935(3) = 215326, so a(3) = ord(2,215326/2) = 165.

Prog

(PARI) list(lim) = my(v=[], d); forstep(k=1, lim, 2, if((2*k-1)%(d=znorder(Mod(2, k)))==0, v=concat(v, d))); v \\ gives a(n) for A347906(n) <= lim

Crossrefs

Cf. A006935, A347906, A350083, A306413, A306414.

Sequence in context: A216940 A200578 A200808 * A280325 A045026 A319727

Adjacent sequences: A350081 A350082 A350083 * A350085 A350086 A350087

Keyword

nonn

Author

Jianing Song, Dec 12 2021

Status

approved