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A058943
Coefficients of irreducible polynomials over GF(2) listed in lexicographic order.
22
10, 11, 111, 1011, 1101, 10011, 11001, 11111, 100101, 101001, 101111, 110111, 111011, 111101, 1000011, 1001001, 1010111, 1011011, 1100001, 1100111, 1101101, 1110011, 1110101, 10000011, 10001001, 10001111, 10010001
OFFSET
1,1
COMMENTS
Church's table extends through degree 11.
REFERENCES
R. Lidl and H. Niederreiter, Finite Fields, Addison-Wesley, 1983, Table C, pp. 553-555.
EXAMPLE
The first few are x, x+1; x^2+x+1; x^3+x+1, x^3+x^2+1; ... Note that x is irreducible but not primitive.
MATHEMATICA
Do[a = Reverse[ IntegerDigits[n, 2]]; b = {0}; l = Length[a]; k = 1; While[k < l + 1, b = Append[b, a[[k]]*x^(k - 1) ]; k++ ]; b = Apply[Plus, b]; c = Factor[b, Modulus -> 2]; If[b == c, Print[ FromDigits[ IntegerDigits[n, 2]]]], {n, 3, 250, 2} ]
PROG
(PARI)
seq(N, p=2, maxdeg=oo) = {
my(a = List(), k=0, d=0);
while (d++ <= maxdeg,
for (n=p^d, 2*p^d-1, my(f=Mod(Pol(digits(n, p)), p));
if(polisirreducible(f), listput(a, subst(lift(f), 'x, 10)); k++);
if(k >= N, break(2))));
Vec(a);
};
seq(27) \\ Gheorghe Coserea, May 28 2018
CROSSREFS
Converted to decimal: A014580.
Irreducible over GF(2), GF(3), GF(4), GF(5), GF(7): this sequence, A058944, A058948, A058945, A058946. Primitive irreducible over GF(2), GF(3), GF(4), GF(5), GF(7): A058947, A058949, A058952, A058950, A058951.
Sequence in context: A287626 A059458 A063697 * A222473 A361990 A335801
KEYWORD
nonn,easy,nice
AUTHOR
N. J. A. Sloane, Jan 13 2001
STATUS
approved