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A284660
Terms of A161897 that are not in A005385.
1
3083, 4931, 6563, 9923, 166667, 865643, 1306667, 2266883, 3367367, 3906563, 4128959, 5493179, 5591039, 6040187, 9122963, 9402179, 9871403, 10174343, 13081379, 13756403, 14924003, 16550243, 24165287, 29492747, 32140859, 34633427, 38425643, 42249587, 42258779, 43014659, 45067523, 52678643
OFFSET
1,1
COMMENTS
Primes p such that q = (p-1)/2 is composite, 3^q == 1 (mod p) and 3^(q-1) == 1 (mod p-1).
All terms == 5 (mod 6).
LINKS
EXAMPLE
p = 3083 is in the sequence because it is prime, q = (3083-1)/2 = 23*67 is composite, 3^q == 1 (mod p) and 3^(q-1) == 1 mod (p-1).
MAPLE
filter:= p -> isprime(p) and not isprime((p-1)/2) and
3&^((p-3)/2) mod (p-1) = 1 and
3 &^((p-1)/2) mod p = 1;
select(filter, [seq(p, p=5..10^7, 6)]); # Robert Israel, Mar 31 2017
CROSSREFS
Sequence in context: A045083 A186470 A322607 * A234781 A045079 A195811
KEYWORD
nonn
AUTHOR
Robert Israel, Mar 31 2017
STATUS
approved