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 1-4 of 4 results.
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