

A000020


Number of primitive polynomials of degree n over GF(2).


10



2, 1, 2, 2, 6, 6, 18, 16, 48, 60, 176, 144, 630, 756, 1800, 2048, 7710, 7776, 27594, 24000, 84672, 120032, 356960, 276480, 1296000, 1719900, 4202496, 4741632, 18407808, 17820000, 69273666, 67108864, 211016256, 336849900, 929275200, 725594112, 3697909056
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

The initial 2 should really be a 1. See A011260 for official version.


REFERENCES

E. R. Berlekamp, Algebraic Coding Theory, McGrawHill, NY, 1968, p. 84.
T. L. Booth, An analytical representation of signals in sequential networks, pp. 3013240 of Proceedings of the Symposium on Mathematical Theory of Automata. New York, N.Y., 1962. Microwave Research Institute Symposia Series, Vol. XII; Polytechnic Press of Polytechnic Inst. of Brooklyn, Brooklyn, N.Y. 1963 xix+640 pp. See p. 303.
W. W. Peterson and E. J. Weldon, Jr., ErrorCorrecting Codes. MIT Press, Cambridge, MA, 2nd edition, 1972, p. 476.
M. P. Ristenblatt, PseudoRandom Binary Coded Waveforms, pp. 274314 of R. S. Berkowitz, editor, Modern Radar, Wiley, NY, 1965; see p. 296.


LINKS



MATHEMATICA



PROG

(PARI) a(n)=if(n==1, 2, eulerphi(2^n1)/n) \\ Hauke Worpel (thebigh(AT)outgun.com), Jun 10 2008


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



