(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
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