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A074967
a(n) = least k such that n^n - k is prime.
8
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
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
Sequence in context: A085428 A053025 A010664 * A021877 A355677 A359179
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