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A323101 Numbers k such that 403*2^k+1 is prime. 1
2, 4, 6, 14, 16, 32, 40, 74, 110, 134, 252, 280, 306, 356, 410, 692, 760, 1220, 1286, 1742, 2060, 2514, 3632, 7104, 7376, 10220, 10980, 18914, 20472, 20676, 22456, 24122, 40834, 42110, 44182, 44814, 45852, 60030, 67826, 68360, 87434, 94386, 158774, 180520 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Jeppe Stig Nielsen, Table of n, a(n) for n = 1..58 (terms n = 1..56 from Robert Price)

Ray Ballinger, Proth Search Page

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for 300 < k < 600

Y. Gallot, Proth.exe: Windows Program for Finding Large Primes

Wilfrid Keller, List of primes k.2^n - 1 for k < 300

Eric Weisstein's World of Mathematics, Proth Prime

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

MAPLE

select(k->isprime(403*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 04 2019

MATHEMATICA

Select[Range[1000], PrimeQ[403*2^# + 1] &]

CROSSREFS

Sequence in context: A027712 A282139 A138307 * A124693 A095698 A277909

Adjacent sequences:  A323098 A323099 A323100 * A323102 A323103 A323104

KEYWORD

nonn,hard

AUTHOR

Robert Price, Jan 04 2019

STATUS

approved

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Last modified January 23 04:16 EST 2020. Contains 331168 sequences. (Running on oeis4.)