

A127875


Numbers x for which (x^3)/2+(3x^2)/2+3x+3 is prime.


6



2, 4, 7, 8, 10, 11, 20, 23, 26, 28, 31, 34, 44, 50, 56, 62, 71, 74, 76, 79, 82, 83, 88, 91, 103, 104, 110, 112, 118, 122, 131, 134, 139, 140, 142, 148, 152, 163, 170, 175, 176, 179, 199, 202, 206, 226, 227, 235, 238, 239, 242, 244, 266, 271, 274, 278, 296, 299
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

Generating polynomial is Schur's polynomial of degree 3. Schur's polynomials n degree are nth first term of series expansion of e^x function. All polynomials are nonreducible 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

Table of n, a(n) for n=1..58.


MATHEMATICA

a = {}; Do[If[PrimeQ[3 + 3 x + (3 x^2)/2 + x^3/2], AppendTo[a, x]], {x, 1, 300}]; a


CROSSREFS

Cf. A127873, A127874.
Sequence in context: A325419 A139212 A175282 * A056231 A248637 A131346
Adjacent sequences: A127872 A127873 A127874 * A127876 A127877 A127878


KEYWORD

nonn


AUTHOR

Artur Jasinski, Feb 04 2007


STATUS

approved



