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

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A262239 Number of (n+3)X(4+3) 0..1 arrays with each row and column divisible by 11, read as a binary number with top and left being the most significant bits. 1
12, 31, 238, 1306, 10747, 77490, 778464, 4345849, 31098659, 251964601, 2327886878 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A262240.

LINKS

Table of n, a(n) for n=1..11.

Michael S. Branicky, Python program

EXAMPLE

Some solutions for n=5

..0..0..1..0..1..1..0....0..0..1..0..1..1..0....0..0..1..0..1..1..0

..0..1..0..0..0..0..1....1..1..0..0..0..1..1....1..1..1..1..0..0..1

..0..1..1..0..1..1..1....0..1..1..0..1..1..1....0..1..0..0..0..0..1

..0..1..1..0..1..1..1....1..0..0..0..0..1..0....1..1..1..1..0..0..1

..1..1..0..0..0..1..1....1..1..0..0..0..1..1....1..1..1..1..0..0..1

..0..0..0..0..0..0..0....0..1..1..0..1..1..1....0..0..1..0..1..1..0

..1..0..0..0..0..1..0....0..1..0..0..0..0..1....0..0..0..0..0..0..0

..1..1..0..0..0..1..1....0..0..1..0..1..1..0....0..1..0..0..0..0..1

PROG

(Python) # see link for faster program

from itertools import product

def a(n):

count = 0

mn, mx = min(n+3, 7), max(n+3, 7)

cands = [bin(m)[2:].zfill(mn) for m in range(0, 2**mn, 11)]

for arr in product(cands, repeat=mx):

vecs = ("".join(arr[i][j] for i in range(mx)) for j in range(mn))

if all(int(v, 2)%11 == 0 for v in vecs):

count += 1

return count

print([a(n) for n in range(1, 4)]) # Michael S. Branicky, Dec 31 2021

CROSSREFS

Cf. A262240.

Sequence in context: A008841 A038624 A302362 * A074299 A118528 A031118

Adjacent sequences: A262236 A262237 A262238 * A262240 A262241 A262242

KEYWORD

nonn,more

AUTHOR

R. H. Hardin, Sep 15 2015

STATUS

approved

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 December 4 09:27 EST 2022. Contains 358556 sequences. (Running on oeis4.)