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A135843
Prime numbers p of the form 10k+1 for which the pentanacci quintic polynomial x^5-x^4-x^3-x^2-x-1 modulus p is factorizable into five binomials.
6
691, 8311, 11731, 17291, 25111, 34421, 40531, 41131, 44971, 47521, 51341, 64891, 70111, 74161, 75991, 76261, 86441, 88471, 99611, 106121, 110251, 112121, 117671, 118171, 133241, 139661, 145451, 156941, 161591, 161641, 164051, 164471, 167071, 172871, 175631, 184291, 194981, 199961, 200171
OFFSET
1,1
COMMENTS
According to class field theory each quintic polynomial is completely reducible modulo some prime number p of the form 10k+1.
REFERENCES
S. Kobayashi & H. Nakagawa, Resolution of Solvable Quintic Equation, Math. Japonica Vol. 87, No 5 (1992), pp. 883-886.
LINKS
MATHEMATICA
a = {}; Do[If[PrimeQ[10n + 1], poly = PolynomialMod[x^5-x^4-x^3-x^2-x-1, 10n + 1]; c = FactorList[poly, Modulus -> 10n + 1]; If[Sum[c[[m]][[2]], {m, 1, Length[c]}] == 6, AppendTo[a, 10n + 1]]], {n, 1, 10000}]; a
CROSSREFS
Cf. A135842.
Sequence in context: A231273 A156036 A029814 * A130662 A029828 A288837
KEYWORD
nonn
AUTHOR
Artur Jasinski, Dec 01 2007
EXTENSIONS
Terms a(20) and beyond from G. C. Greubel, Dec 06 2016
STATUS
approved