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Revision History for A091245

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A091245

Number of reducible GF(2)[X]-polynomials in range [0,n].
(history; published version)

#8 by Charles R Greathouse IV at Wed Sep 02 10:52:02 EDT 2015

STATUS

editing

approved

#7 by Charles R Greathouse IV at Wed Sep 02 10:52:00 EDT 2015

PROG

(PARI) first(n)=my(s); concat([0, 0], vector(n-1, k, s += !polisirreducible(Pol(binary(k+1))*Mod(1, 2)))) \\ Charles R Greathouse IV, Sep 02 2015

STATUS

approved

editing

#6 by Russ Cox at Sat Mar 31 14:02:20 EDT 2012

AUTHOR

_Antti Karttunen (His-Firstname.His-Surname(AT)iki.fi), _, Jan 03 2004

Discussion

Sat Mar 31

14:02

OEIS Server: https://oeis.org/edit/global/913

#5 by Russ Cox at Sun Jul 10 18:42:46 EDT 2011

LINKS

<a href="/Sindx_index/Ge.html#GF2X">Index entries for sequences operating on GF(2)[X]-polynomials</a>

Discussion

Sun Jul 10

18:42

OEIS Server: https://oeis.org/edit/global/43

#4 by N. J. A. Sloane at Thu Nov 11 07:34:06 EST 2010

LINKS

A. Karttunen, <a href="/A091247/a091247.scm.txt">Scheme-program for computing this sequence.</a>

<a href="/Sindx_Ge.html#GF2X">Index entries for sequences operating on GF(2)[X]-polynomials</a>

KEYWORD

nonn,new

nonn

#3 by N. J. A. Sloane at Fri Feb 27 03:00:00 EST 2009

LINKS

A. Karttunen, <a href="http://www.research.att.com/~njas/sequences/a091247.scm.txt">Scheme-program for computing this sequence.</a>

<a href="http://www.research.att.com/~njas/sequences/Sindx_Ge.html#GF2X">Index entries for sequences operating on GF(2)[X]-polynomials</a>

KEYWORD

nonn,new

nonn

#2 by N. J. A. Sloane at Tue Jan 24 03:00:00 EST 2006

LINKS

A. Karttunen, <a href="http://www.research.att.com/~njas/sequences/GF2Xfunsa091247.scm.txt">Scheme-program for computing this sequence.</a>

KEYWORD

nonn,new

nonn

#1 by N. J. A. Sloane at Thu Feb 19 03:00:00 EST 2004

NAME

Number of reducible GF(2)[X]-polynomials in range [0,n].

DATA

0, 0, 0, 0, 1, 2, 3, 3, 4, 5, 6, 6, 7, 7, 8, 9, 10, 11, 12, 12, 13, 14, 15, 16, 17, 17, 18, 19, 20, 21, 22, 22, 23, 24, 25, 26, 27, 27, 28, 29, 30, 30, 31, 32, 33, 34, 35, 35, 36, 37, 38, 39, 40, 41, 42, 42, 43, 44, 45, 45, 46, 46, 47, 48, 49, 50, 51, 51, 52, 53, 54, 55, 56, 56

OFFSET

0,6

COMMENTS

Analogous to A065855.

LINKS

A. Karttunen, <a href="http://www.research.att.com/~njas/sequences/GF2Xfuns.scm.txt">Scheme-program for computing this sequence.</a>

<a href="http://www.research.att.com/~njas/sequences/Sindx_Ge.html#GF2X">Index entries for sequences operating on GF(2)[X]-polynomials</a>

EXAMPLE

In range [0,8] there are the following four reducible polynomials: 4,5,6,8 thus a(8) = 4.

CROSSREFS

Partial sums of A091247. Cf. A091242.

KEYWORD

nonn

AUTHOR

Antti Karttunen (His-Firstname.His-Surname(AT)iki.fi), Jan 03 2004

STATUS

approved