A226267 Number of additive Z_2 Z_8 codes of a certain type (see Siap-Aydogdu for precise definition).

2352, 9721600, 449914060800, 280154359021436928, 2560999281742478158331904, 358821757256355942900943762227200, 787296929540087707656924853902883002777600, 27343461806425897751473875699316284363491645025419264

Offset

1,1

Comments

N2×8(r+2, 2r+1; r, 0, 1, r) r>=1. (Siap-Aydogdu Table 1)

Links

Lars Blomberg, Table of n, a(n) for n = 1..30

I. Siap and I. Aydogdu, Counting The Generator Matrices of Z_2 Z_8 Codes, arXiv preprint arXiv:1303.6985 [math.CO], 2013.

Mathematica

QP = QPochhammer;
a[n_] := (2^(2n+1)(8^(n+1))^n (2^(2n+1)-1) QP[2^(-2-n), 2, n] QP[4^-n, 2, n])/((2^(n+1))^n QP[2^(-n), 2, n]^2 2^(n-1));
Array[a, 8] (* Jean-François Alcover, Sep 01 2018 *)

Crossrefs

Cf. A226262, A226263, A226264, A226265, A226266, A226268.

Sequence in context: A219193 A063517 A035874 * A251295 A220626 A136420

Adjacent sequences: A226264 A226265 A226266 * A226268 A226269 A226270

Keyword

nonn

Author

N. J. A. Sloane, Jun 02 2013

Extensions

Terms a(4) and beyond from Lars Blomberg, Jun 14 2017

Status

approved