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A323103
Numbers k such that 407*2^k+1 is prime.
1
3, 11, 15, 23, 75, 119, 159, 215, 227, 235, 931, 979, 1147, 1727, 2495, 2827, 3219, 4787, 6191, 11815, 12823, 18619, 21203, 24547, 34115, 61455, 71495, 105091, 109115, 120827, 121203, 149607, 198907, 211167, 499431, 541955, 584491, 864871, 1013603, 1171719
OFFSET
1,1
MAPLE
select(k->isprime(407*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 04 2019
MATHEMATICA
Select[Range[1000], PrimeQ[407*2^# + 1] &]
CROSSREFS
Sequence in context: A331831 A357440 A186302 * A046159 A022410 A146254
KEYWORD
nonn,hard
AUTHOR
Robert Price, Jan 04 2019
STATUS
approved