login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A262846 Number of (n+2)X(4+2) 0..1 arrays with each row divisible by 7 and column not divisible by 7, read as a binary number with top and left being the most significant bits. 1

%I

%S 318,3181,37635,420654,3896365,39348387,417279054,3999504445,

%T 39913429587,409857534030,4017392736541,40104536998707,

%U 405732145282158,4021339824862381,40178930760566115,403823141865184494

%N Number of (n+2)X(4+2) 0..1 arrays with each row divisible by 7 and column not divisible by 7, read as a binary number with top and left being the most significant bits.

%C Column 4 of A262849.

%H R. H. Hardin, <a href="/A262846/b262846.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 13*a(n-1) -30*a(n-2) +775*a(n-3) -10075*a(n-4) +23250*a(n-5) -187265*a(n-6) +2434445*a(n-7) -5617950*a(n-8) +18375455*a(n-9) -238880915*a(n-10) +551263650*a(n-11) -585288123*a(n-12) +7608745599*a(n-13) -17558643690*a(n-14) -12851058675*a(n-15) +167063762775*a(n-16) -385531760250*a(n-17) +757921180765*a(n-18) -9852975349945*a(n-19) +22737635422950*a(n-20) -1115961555955*a(n-21) +14507500227415*a(n-22) -33478846678650*a(n-23) -69403913471776*a(n-24) +902250875133088*a(n-25) -2082117404153280*a(n-26) -67517783528000*a(n-27) +877731185864000*a(n-28) -2025533505840000*a(n-29)

%e Some solutions for n=3

%e ..0..1..1..1..0..0....1..1..1..0..0..0....1..0..0..0..1..1....0..0..0..0..0..0

%e ..1..0..0..0..1..1....0..0..0..1..1..1....1..0..1..0..1..0....1..0..0..0..1..1

%e ..1..1..1..1..1..1....0..0..0..0..0..0....1..1..0..0..0..1....0..1..1..1..0..0

%e ..0..1..0..1..0..1....0..0..1..1..1..0....1..0..0..0..1..1....0..1..0..1..0..1

%e ..1..1..0..0..0..1....0..0..0..0..0..0....0..1..1..1..0..0....1..0..1..0..1..0

%Y Cf. A262849.

%K nonn

%O 1,1

%A _R. H. Hardin_, Oct 03 2015

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 30 18:52 EDT 2022. Contains 354945 sequences. (Running on oeis4.)