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A139686
Odd multiplicative orders of 2 modulo primes.
2
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
1,1
COMMENTS
Subsequence of A014664, consisting of odd elements.
LINKS
FORMULA
a(n) = multiplicative order of 2 modulo A014663(n).
MATHEMATICA
p = Select[Range[1000], PrimeQ]; Select[MultiplicativeOrder[2, #] & /@ p, OddQ] (* Amiram Eldar, Jul 30 2020 *)
PROG
(PARI) forprime(p=3, 10^5, z=znorder(Mod(2, p)); if(z%2, print1(z, ", ")))
CROSSREFS
Sequence in context: A084462 A156320 A134969 * A212782 A130537 A212402
KEYWORD
nonn
AUTHOR
Max Alekseyev, Apr 29 2008
STATUS
approved