A076185
Numbers n such that n!! + 2 is prime.
Original entry on oeis.org
0, 1, 3, 5, 7, 9, 21, 23, 27, 57, 75, 103, 169, 219, 245, 461, 695, 1169, 3597, 3637, 7495, 27743, 28799, 32501
Offset: 1
One more term from Herman Jamke (hermanjamke(AT)fastmail.fm), Dec 30 2007
A076186
Numbers n such that n!! + 2^2 is prime.
Original entry on oeis.org
0, 1, 3, 5, 7, 11, 17, 29, 39, 43, 73, 93, 315, 549, 2059, 5543, 6937, 22819, 34523
Offset: 1
6937 from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
Corrected by Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
A076189
Numbers k such that k!! + 2^4 is prime.
Original entry on oeis.org
0, 1, 3, 5, 13, 17, 25, 27, 39, 45, 47, 53, 177, 217, 401, 637, 729, 787, 843, 3407, 8835, 10283, 14061, 21951
Offset: 1
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select(t -> isprime(doublefactorial(t)+16), [$0..1000]); # Robert Israel, Jan 19 2015
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lst={}; Do[If[PrimeQ[n!!+2^4], AppendTo[lst, n]], {n, 0, 50000}]; lst
8835 from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
A076190
Numbers n such that n!! + 2^5 is prime.
Original entry on oeis.org
5, 7, 9, 11, 15, 21, 33, 41, 43, 45, 67, 93, 117, 327, 363
Offset: 1
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lst={}; Do[If[PrimeQ[n!!+2^5], AppendTo[lst, n]], {n, 0,50000}]; lst
Select[Range[400],PrimeQ[#!!+32]&] (* Harvey P. Dale, Jul 22 2021 *)
A076193
Numbers k such that k!! + 2^6 is prime.
Original entry on oeis.org
3, 5, 9, 11, 17, 19, 23, 51, 219, 421, 2845, 4691, 10617
Offset: 1
A076194
Numbers k such that k!! + 2^7 is prime.
Original entry on oeis.org
3, 7, 17, 19, 31, 43, 51, 163, 215, 269, 297, 457, 599, 633, 795, 999, 1027, 1261, 2567, 14315, 39505, 44725
Offset: 1
A076195
Numbers k such that k!! + 2^8 is prime.
Original entry on oeis.org
0, 1, 5, 9, 11, 13, 23, 135, 187, 215, 233, 313, 333, 493, 1459, 2753, 2813, 6411, 31191, 38303, 41487
Offset: 1
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lst={}; Do[If[PrimeQ[n!!+2^8], AppendTo[lst, n]], {n, 0, 50000}]; lst
a(18) from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
a(1)=0 prepended and a(19)-a(21) from
Robert Price, Jan 14 2015
A076196
Numbers k such that k!! + 2^9 is prime.
Original entry on oeis.org
7, 13, 15, 19, 25, 133, 135, 199, 223, 297, 299, 511, 15263, 16491, 18967, 32455
Offset: 1
A076197
Numbers k such that k!! + 2^10 is prime.
Original entry on oeis.org
5, 7, 21, 33, 153, 167, 171, 391, 789, 1323, 2645, 8655, 10153, 39967, 45369, 47599
Offset: 1
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lst={};Do[If[PrimeQ[n!!+2^10], (*Print[n];*)AppendTo[lst, n]], {n, 6!}];lst (* Vladimir Joseph Stephan Orlovsky, Aug 26 2008 *)
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from gmpy2 import is_prime
A076197_list, g, h = [], 1, 1024
for i in range(3,10**5,2):
g *= i
if is_prime(g+h):
A076197_list.append(i) # Chai Wah Wu, May 31 2015
8655 from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
A257864
Numbers n such that n!! - 2^7 is prime.
Original entry on oeis.org
11, 13, 21, 47, 59, 77, 109, 129, 155, 163, 245, 337, 511, 1417, 3013, 3757, 4989, 8977, 12479, 12869
Offset: 1
Cf.
A080778,
A076185,
A076186,
A076188,
A076189,
A076190,
A076193,
A076194,
A076195,
A076196,
A076197 (other forms of n!!+2^k)
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Select[Range[0, 50000], #!! - 128 > 0 && PrimeQ[#!! - 128] &]
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is(n)=ispseudoprime(prod(i=0,(n-1)\2, n-2*i)-128) \\ Charles R Greathouse IV, May 11 2015
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use ntheory ":all"; use Math::GMPz;
sub mf2 { my($n,$P)=(shift,Math::GMPz->new(1)); $P *= $n-($_<<1) for 0..($n-1)>>1; $P; }
for (1..100000) { say if is_prob_prime(mf2($)-128) } # _Dana Jacobsen, May 13 2015
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from gmpy2 import is_prime, mpz
A257864_list, g, h = [], mpz(105), mpz(128)
for i in range(9,10**5,2):
g *= i
if is_prime(g-h):
A257864_list.append(i) # Chai Wah Wu, May 12 2015
Showing 1-10 of 13 results.
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