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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 (list; graph; refs; listen; history; text; internal format)
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.
LINKS
T. D. Noe, Table of n, a(n) for n=1..1377 (through degree 13)
R. Church, Tables of irreducible polynomials for the first four prime moduli, Annals Math., 36 (1935), 198-209.
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

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Last modified April 23 08:33 EDT 2024. Contains 371905 sequences. (Running on oeis4.)