A074967 a(n) = least k such that n^n - k is prime.

1, 4, 5, 4, 7, 2, 3, 10, 33, 42, 19, 12, 17, 52, 59, 18, 65, 2, 51, 2, 23, 120, 35, 2, 63, 10, 39, 186, 7, 74, 47, 200, 53, 24, 19, 48, 333, 56, 57, 192, 127, 348, 63, 124, 213, 60, 359, 2, 213, 2, 387, 526, 269, 252, 863, 16, 131, 370, 503, 294, 83, 68, 317

Offset

2,2

Links

Seiichi Manyama, Table of n, a(n) for n = 2..500

Mathematica

PrimePrevDelta[n_]:=Module[{k}, k=n-1; While[ !PrimeQ[k], k-- ]; k=n-k]; lst={}; Do[AppendTo[lst, PrimePrevDelta[n^n]], {n, 2, 5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jun 11 2009 *)
lk[n_]:=Module[{nn=n^n}, nn-NextPrime[nn, -1]]; Array[lk, 70, 2] (* Harvey P. Dale, Jan 20 2019 *)

Prog

(PARI) a(n)=(x->x-precprime(x))(n^n) \\ Charles R Greathouse IV, Nov 25 2014

Crossrefs

Cf. A033933, A074966.

Sequence in context: A085428 A053025 A010664 * A021877 A355677 A359179

Adjacent sequences: A074964 A074965 A074966 * A074968 A074969 A074970

Keyword

nonn

Author

Zak Seidov, Oct 03 2002

Extensions

More terms from Robert G. Wilson v, Oct 04 2002

Offset corrected by R. J. Mathar, Jun 12 2009

Status

approved