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A349722 Primes p such that the greatest common divisor of 2^p+1 and 3^p+1 is composite. 2
2243399, 2334547, 2743723, 3932207, 4623107, 4716343, 5482423, 5993411, 6490151, 7156769, 7187743, 8795167, 9026987, 9608843, 9923209 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Carlos Rivera, Puzzle 1064. GCD(2^p+1,3^p+1), The Prime Puzzles and Problems Connection.
PROG
(PARI) isok(p) = if (isprime(p), my(g=gcd(2^p+1, 3^p+1)); (g>1) && !isprime(g));
CROSSREFS
Subsequence of A260674.
Cf. A066803.
Sequence in context: A224629 A224636 A046444 * A180940 A089445 A089446
KEYWORD
nonn,more
AUTHOR
Michel Marcus, Nov 27 2021
EXTENSIONS
a(4)-a(7) after update of Rivera link from Martin Ehrenstein, Dec 04 2021
a(8)-a(9) from Shyam Sunder Gupta, Dec 04 2021
a(10)-a(15) from Martin Ehrenstein, Dec 05 2021
STATUS
approved

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Last modified June 25 06:01 EDT 2024. Contains 373697 sequences. (Running on oeis4.)