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A283553 Numbers k such that k![4] + 2 is prime, where k![4] = A007662(k) = quadruple factorial. 10
0, 1, 3, 5, 7, 9, 11, 13, 15, 19, 27, 29, 31, 43, 53, 75, 143, 169, 185, 235, 259, 363, 365, 457, 493, 573, 777, 1273, 1275, 1865, 3621, 4523, 5291, 5845, 7185, 10183, 12845, 15057, 16281, 17945, 18771, 22479, 27235, 28089, 31557, 39163, 45709, 46329, 52211, 77779 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
a(51) > 10^5.
The first 10 primes associated with this sequence: 3, 3, 5, 7, 23, 47, 233, 587, 3467, 65837.
LINKS
C. Caldwell and H. Dubner (Eds): The top ten prime numbers: from the unpublished collections of R. Ondrejka (May 2001), Table 21 F, p. 75
MATHEMATICA
MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n - k, k]];
Select[Range[0, 50000], PrimeQ[MultiFactorial[#, 4] + 2] &]
Select[Range[0, 78000], PrimeQ[Times@@Range[#, 1, -4]+2]&] (* Harvey P. Dale, Aug 16 2023 *)
CROSSREFS
Sequence in context: A192861 A333854 A192868 * A081110 A143449 A033034
KEYWORD
nonn
AUTHOR
Robert Price, Mar 10 2017
EXTENSIONS
a(49)-a(50) from Robert Price, Aug 12 2017
STATUS
approved

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Last modified July 25 05:51 EDT 2024. Contains 374586 sequences. (Running on oeis4.)