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A111190
Numbers k such that floor(Pi^k - e^k) is prime.
0
2, 5, 6, 73, 1547, 2714, 4937, 5212, 58775
OFFSET
1,1
COMMENTS
No more terms through 10000.
If it exists, a(10) > 90000. - J.W.L. (Jan) Eerland, Sep 29 2022
EXAMPLE
floor(Pi^6 - e^6) = 557 is prime, hence 6 is a term.
MATHEMATICA
$MaxExtraPrecision = 10^6; Do[k = Floor[Pi^n - E^n]; If[PrimeQ[k], Print[n]], {n, 1, 10000}]
Select[Range[6000], PrimeQ[Floor[Pi^#-E^#]]&] (* Harvey P. Dale, Jun 02 2014 *)
ParallelTable[If[PrimeQ[Floor[Pi^k-E^k]], k, Nothing], {k, 0, 9*10^4}]//.{}->Nothing (* J.W.L. (Jan) Eerland, Sep 29 2022 *)
CROSSREFS
Cf. A181052.
Sequence in context: A288799 A281378 A219117 * A244434 A176007 A009376
KEYWORD
nonn,hard,more
AUTHOR
Ryan Propper, Oct 23 2005
EXTENSIONS
a(9) from J.W.L. (Jan) Eerland, Sep 29 2022
STATUS
approved