1,1

Odd numbers n such that A007733(n) = A002326((n-1)/2) is even.

Table of n, a(n) for n=1..64.

A036259 = Select[Range[1, 199, 2], OddQ[MultiplicativeOrder[2, #]] &];

Range[1, A036259[[-1]], 2] ~Complement~ A036259 (* Jean-François Alcover, Dec 20 2017 *)

(PARI) { is_A296243(n) = (n%2) && !(znorder(Mod(2, n))%2); }

Set difference of A005408 and A036259.

Contains A296244 as a subsequence.

The prime terms are given by A014662.

Sequence in context: A304251 A309135 A088607 * A162699 A325129 A173263

Adjacent sequences: A296240 A296241 A296242 * A296244 A296245 A296246

nonn

Max Alekseyev, Dec 09 2017

approved