A226281
Least number k such that 3^(2^i) + k is prime for i = 0,1,..,n-1.
Original entry on oeis.org
2, 2, 2, 2, 58, 440, 18248, 2024098, 4263330280, 22836544460, 40728071843930
Offset: 1
a(5) = 58 because k = 58 is the minimal k such that N = 3^(2^i) + k is prime for i = 0, 1, 2 ,3 ,4; N = 61, 67, 139, 6619, 43046779. But 3^(2^5) + 58 is divisible by 37 and three other primes.
A226707
Least number k such that 5^(2^i) + k is prime for i = 0,1,..,n-1.
Original entry on oeis.org
2, 6, 6, 48, 384, 1518, 2037018, 2037018, 44279730804, 424427587626
Offset: 1
a(5) = 384 because k = 384 is the minimal k such that N = 5^(2^i) + k is prime for i = 0, 1, 2, 3, 4; N = 389, 409, 1009, 391009, 152587891009. But 5^(2^5) + 384 is divisible by 797 and another prime.
A161719
Least number k such that 7^(2^i) + k is prime for i = 0,1,..,n-1.
Original entry on oeis.org
4, 4, 10, 40, 990, 8712, 1691820, 69466840, 6173190532, 4139897208540
Offset: 1
a(5) = 990 because k = 990 is the minimal k such that N = 7^(2^i) + k is prime for i = 0, 1, 2, 3, 4; N = 997, 1039, 3391, 5765791, 33232930570591. But 7^(2^5) + 990 is divisible by 37 and four other primes.
A226708
Least number k such that 6^(2^i) + k is prime for i = 0,1,..,n-1.
Original entry on oeis.org
1, 1, 1, 11, 77, 1081, 142531, 41758027, 1206670783, 10654858617041
Offset: 1
A226745
Least number k such that 9^(2^i) + k is prime for i = 0,1,..,n-1.
Original entry on oeis.org
2, 2, 2, 58, 440, 18248, 1659002, 71997050, 6776406070, 2038979576678
Offset: 1
A226766
Least number k such that 4^(2^i) + k is prime for i = 0,1,..,n-1.
Original entry on oeis.org
1, 1, 1, 1, 15, 93, 53097, 3014907, 2295032545, 46868723367
Offset: 1
Showing 1-6 of 6 results.
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