A122527 and A121231 (number of binary matrices)

Richard Mathar mathar at strw.leidenuniv.nl
Sat Aug 2 22:46:39 CEST 2008

start with the same numbers
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Hi, dear group!

Maybe I've got difficulties understanding
http://research.att.com/~njas/sequences/A122527 "Number of 7 x n binary
Shouldn't this read a(n)=2^(7n)?

I guess I do not understand  "binary matrices" in the same sense as the
author of this series does.

Could someone please enlighten me?


P.S.: Sorry Richard, I can't answer any of your questions until I
understand the sequences.

P.P.S.: If this message reaches you twice, please forgive my mail client
and me! I send this via a poor webmail interface, because my Windows-Thunderbird does not use the correct SMTP-server.

# Richard wrote:
# A comparison of A122527 and A121231 shows that they
# start with the same numbers
# http://research.att.com/~njas/sequences/?q=id:A122527|id:A121231
# Is this some coincidence enforced by the odd-prime dimension
# of the row count? (See also A052264) Can these numbers
# be smaller than those in A055084 for the 6xn matrices although
# the latter are counted with restrictions?
# Richard

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