A110931
Numbers k such that 2*k^k - 1 is prime.
Original entry on oeis.org
2, 3, 357, 1400, 205731, 296598
Offset: 1
3 is in the sequence since 2*3^3 - 1 = 53 is prime.
Numbers k such that b*k^k - b + 1 is prime: this sequence (b=2),
A301521 (b=4),
A302123 (b=6).
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[n: n in [0..500] | IsPrime(2*n^n-1)]; // Vincenzo Librandi, Nov 01 2014
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Select[Range[1000], PrimeQ[2*#^# - 1] &] (* Vaclav Kotesovec, Oct 31 2014 *)
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for(n=1,2000,1;if(isprime(2*n^n-1),print(n))) \\ Ray G. Opao, Oct 23 2014
A302123
Numbers k such that 6*k^k - 5 is prime.
Original entry on oeis.org
2, 3, 4, 7, 8, 9, 33, 138, 251, 467, 489, 9894
Offset: 1
Numbers k such that b*k^k - b + 1 is prime:
A301521 (b=4), this sequence (b=6).
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Select[Range[1, 1000], PrimeQ[6*#^# - 5] &] (* Vaclav Kotesovec, Apr 02 2018 *)
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for(n=0, 300, if(isprime(6*n^n-5), print1(n", ")))
A301520
Numbers k such that 4*k^k + 3 is prime.
Original entry on oeis.org
0, 1, 2, 5, 10, 44, 65, 1424
Offset: 1
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Flatten[{0, Select[Range[1000], PrimeQ[4*#^# + 3] &]}] (* Vaclav Kotesovec, Mar 25 2018 *)
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for(n=0, 100, if(isprime(4*n^n+3), print1(n", ")))
A301870
Primes of form 4*k^k - 3.
Original entry on oeis.org
13, 1021, 12497, 3294169, 1365711509456878229586586894333
Offset: 1
A302134
Numbers k such that 9*k^k - 8 is prime.
Original entry on oeis.org
7, 9, 11, 353, 7133
Offset: 1
A302136
Numbers k such that 10*k^k - 9 is prime.
Original entry on oeis.org
2, 4, 14, 80, 1133, 4120
Offset: 1
A302132
Numbers k such that 3*k^k - 2 is prime.
Original entry on oeis.org
A302133
Numbers k such that 8*k^k - 7 is prime.
Original entry on oeis.org
10, 800, 1266, 1395
Offset: 1
Showing 1-8 of 8 results.
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