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A034188 Number of binary codes of length 3 with n words. 65

%I

%S 1,1,3,3,6,3,3,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

%T 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

%U 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

%N Number of binary codes of length 3 with n words.

%D H. Fripertinger, Enumeration, construction and random generation of block codes, Designs, Codes, Crypt., 14 (1998), 213-219.

%H H. Fripertinger, <a href="http://www.mathe2.uni-bayreuth.de/frib/codes/tables.html">Isometry Classes of Codes</a>

%F a(n)=[C(2*n,n) mod 2]+{C[(n+1)^2,n+3] mod 2}+3*[C(n^2,n+2) mod 2]+3*{C[(n+11)^4,n+13] mod 2}+6*{C[(n+10)^4,n+12] mod 2}+3*{C[(n+9)^4,n+11] mod 2}+3*{C[(n+8)^4,n+10] mod 2}+{C[(n+7)^4,n+9] mod 2}+{C[(n+6)^4,n+8] mod 2} - _Paolo P. Lava_, Jan 07 2008

%Y Cf. A034189, A034190, A034191, A034192, A034193, A034194, A034195, A034196, A034197.

%Y A row of A039754.

%K nonn

%O 0,3

%A _N. J. A. Sloane_.

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Last modified April 13 02:47 EDT 2021. Contains 342934 sequences. (Running on oeis4.)