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%I #9 Dec 31 2021 06:06:22
%S 12,31,238,1306,10747,77490,778464,4345849,31098659,251964601,
%T 2327886878
%N 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.
%C Column 4 of A262240.
%H Michael S. Branicky, <a href="/A262239/a262239.py.txt">Python program</a>
%e Some solutions for n=5
%e ..0..0..1..0..1..1..0....0..0..1..0..1..1..0....0..0..1..0..1..1..0
%e ..0..1..0..0..0..0..1....1..1..0..0..0..1..1....1..1..1..1..0..0..1
%e ..0..1..1..0..1..1..1....0..1..1..0..1..1..1....0..1..0..0..0..0..1
%e ..0..1..1..0..1..1..1....1..0..0..0..0..1..0....1..1..1..1..0..0..1
%e ..1..1..0..0..0..1..1....1..1..0..0..0..1..1....1..1..1..1..0..0..1
%e ..0..0..0..0..0..0..0....0..1..1..0..1..1..1....0..0..1..0..1..1..0
%e ..1..0..0..0..0..1..0....0..1..0..0..0..0..1....0..0..0..0..0..0..0
%e ..1..1..0..0..0..1..1....0..0..1..0..1..1..0....0..1..0..0..0..0..1
%o (Python) # see link for faster program
%o from itertools import product
%o def a(n):
%o count = 0
%o mn, mx = min(n+3, 7), max(n+3, 7)
%o cands = [bin(m)[2:].zfill(mn) for m in range(0, 2**mn, 11)]
%o for arr in product(cands, repeat=mx):
%o vecs = ("".join(arr[i][j] for i in range(mx)) for j in range(mn))
%o if all(int(v, 2)%11 == 0 for v in vecs):
%o count += 1
%o return count
%o print([a(n) for n in range(1, 4)]) # _Michael S. Branicky_, Dec 31 2021
%Y Cf. A262240.
%K nonn,more
%O 1,1
%A _R. H. Hardin_, Sep 15 2015
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