This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A171699 #11 Dec 01 2023 03:25:52 %S A171699 1,1,1,1,2,1,1,3,3,1,1,4,7,4,1,1,5,14,14,5,1,1,6,25,45,25,6,1,1,7,41, %T A171699 130,130,41,7,1,1,8,63,336,650,336,63,8,1,1,9,92,785,2942,2942,785,92, %U A171699 9,1,1,10,129,1682,11819,24520,11819,1682,129,10,1,1,11,175 %N A171699 Square array of number of distinct m X n (0,1) matrices after iterated double sorting, read by antidiagonals. %C A171699 T(m,n) gives the number of distinct results obtained by repeatedly sorting the m X n (0,1) matrices by columns & then rows until reaching a fixed point. Its diagonal is A089006. %e A171699 Array begins: %e A171699 1,1,1,1,1,... %e A171699 1,2,3,4,5,... %e A171699 1,3,7,14,25,... %e A171699 1,4,14,45,130,... %e A171699 1,5,25,130,650,... %o A171699 (Haskell) %o A171699 -- with the function "t" producing the array. %o A171699 import List %o A171699 prod = foldr (\x xs -> [y:ys | y <- x, ys <- xs]) [[]] %o A171699 f xs = let ys = sort (transpose (sort (transpose xs))) in if xs == ys then xs else f ys %o A171699 t m n = length $ nub $ map f $ prod (replicate m (prod (replicate n [0,1]))) %Y A171699 Cf. A089006. %K A171699 nonn,tabl %O A171699 0,5 %A A171699 Randy Compton (RANDYRulerOfZexernet(AT)gmail.com), Dec 15 2009 %E A171699 Corrected & extended by Randy Compton (RANDYRulerOfZexernet(AT)gmail.com), Dec 18 2009