%I A128901
%S A128901 0,1,2,4,8,16,32,63,128,255,510,1020,2032,4048,8109,16216,32434,
%T A128901 64731,129597,258718,517424,1034430,2067780,4132038,8262934,
%U A128901 16515320,33021972,66029987,132008983,263944002,527772375,1055126462
%N A128901 Number of degree n polynomials over GF(2) (with non-zero constant term) 
               at Hamming distance 1 from some irreducible polynomial.
%H A128901 G. Lee, F. Ruskey and A. Williams, <a href="http://www.cs.uvic.ca/~ruskey/
               Publications/DistGF2/DistGF2.html">Hamming distance from irreducible 
               polynomials over GF(2)</a>
%e A128901 The coefficient vectors of the two degree 3 irreducible polynomials are 
               1011 and 1101. They are at distance one from the two polynomials 
               1001 and 1111; thus a(3) = |{1001,1111}| = 2.
%Y A128901 Sequence in context: A001592 A140134 A049886 this_sequence A025489 A036140 
               A036138
%Y A128901 Adjacent sequences: A128898 A128899 A128900 this_sequence A128902 A128903 
               A128904
%K A128901 nonn
%O A128901 1,3
%A A128901 Frank Ruskey (ruskey(AT)cs.uvic.ca), Apr 22 2007