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A127880 Numbers x for which x^4 + 4x^3 + 12x^2 + 24x + 24 is prime. 5
43, 55, 103, 115, 223, 307, 319, 379, 403, 487, 505, 607, 643, 715, 757, 763, 775, 799, 883, 925, 979, 1063, 1069, 1135, 1147, 1165, 1189, 1279, 1309, 1369, 1543, 1567, 1585, 1627, 1693, 1729, 1783, 1813, 1819, 1855, 1903, 1939, 1945, 2083, 2149, 2155 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Generating polynomial is Schur's polynomial of 4-degree. Schur's polynomials n degree are n-th first term of series expansion of e^x function. All polynomials are non-reducible and belonging to the An alternating Galois transitive group if n is divisible by 4 or to Sn symmetric Galois Group in other case (proof Schur, 1930).
LINKS
MAPLE
select(x->isprime(x^4+4*x^3+12*x^2+24*x+24), [$1..3000]); # Muniru A Asiru, Apr 30 2018
MATHEMATICA
a = {}; Do[If[PrimeQ[24 + 24 x + 12 x^2 + 4 x^3 + x^4], AppendTo[a, x]], {x, 1, 1000}]; a
PROG
(PARI) isok(x) = isprime(x^4 + 4*x^3 + 12*x^2 + 24*x + 24); \\ Michel Marcus, Apr 30 2018
(GAP) Filtered([1..3000], x->IsPrime(x^4+4*x^3+12*x^2+24*x+24)); # Muniru A Asiru, Apr 30 2018
CROSSREFS
Sequence in context: A280388 A180546 A166491 * A078132 A201613 A115404
KEYWORD
nonn
AUTHOR
Artur Jasinski, Feb 04 2007
STATUS
approved

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Last modified April 23 06:04 EDT 2024. Contains 371906 sequences. (Running on oeis4.)