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Number of additive Z_2 Z_8 codes of a certain type (see Siap-Aydogdu for precise definition).
7

%I #20 Jun 30 2023 22:06:55

%S 42,10080,1666560,239984640,32509919232,4278724853760,555283403243520,

%T 71565974364487680,9191877617198825472,1178574993109328855040,

%U 150986631766311048314880,19334549981260177075077120,2475351205805918328572608512,316878801167116801685764177920

%N Number of additive Z_2 Z_8 codes of a certain type (see Siap-Aydogdu for precise definition).

%C N2×8(1, k; 1, 1, 1, 1) where k >= 3. (Siap-Aydogdu p 20)

%H Lars Blomberg, <a href="/A226262/b226262.txt">Table of n, a(n) for n = 1..100</a>

%H I. Siap and I. Aydogdu, <a href="http://arxiv.org/abs/1303.6985">Counting The Generator Matrices of Z_2 Z_8 Codes</a>, arXiv preprint arXiv:1303.6985, 2013

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (240, -17920, 491520, -4194304).

%t a[n_] := 4^(2(n+2)-7)(2^(n+2)-4)(2^(n+2)-2)(2^(n+2)-1);

%t Array[a, 14] (* _Jean-François Alcover_, Sep 01 2018 *)

%Y Cf. A226263-A226268.

%K nonn

%O 1,1

%A _N. J. A. Sloane_, Jun 02 2013

%E Terms a(5) and beyond from _Lars Blomberg_, Jun 14 2017