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%I #15 Feb 04 2020 21:25:00
%S 0,0,0,0,1,0,0,0,0,0,0,0,2,0,0,0,0,1,1,0,0,0,0,0,3,0,0,0,0,0,0,1,1,0,
%T 0,0,0,0,0,1,4,1,0,0,0,0,0,0,0,2,2,0,0,0,0,0,0,0,0,1,5,1,0,0,0,0,0,0,
%U 0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,1,6,1,0
%N T(n, k) = floor(n/m) where m is the least positive integer such that floor(n/m) = floor(k/m). Square array read by antidiagonals, for n >= 0 and k >= 0.
%C For any n > 0, the n-th row has A001651(n) nonzero terms.
%H Rémy Sigrist, <a href="/A331902/b331902.txt">Table of n, a(n) for n = 0..10010</a> (antidiagonals 0..140)
%H Rémy Sigrist, <a href="/A331886/a331886_1.png">Colored representation of T(n, k) for n, k = 0..1000</a> (where the hue is function of T(n, k), red pixels correspond to 0's)
%F T(n, k) = floor(n/A331886(n, k)) = floor(k/A331886(n, k)).
%F T(n, k) = T(k, n).
%F T(n, k) = 0 iff max(n, k) >= 2*min(n, k).
%F T(n, n+1) = A213633(n+1).
%e Array T(n, k) begins (with dots instead of 0's for readability):
%e n\k| 0 1 2 3 4 5 6 7 8 9 10 11 12
%e ---+----------------------------------------------------
%e 0| . . . . . . . . . . . . .
%e 1| . 1 . . . . . . . . . . .
%e 2| . . 2 1 . . . . . . . . .
%e 3| . . 1 3 1 1 . . . . . . .
%e 4| . . . 1 4 2 1 1 . . . . .
%e 5| . . . 1 2 5 1 1 1 1 . . .
%e 6| . . . . 1 1 6 3 2 1 1 1 .
%e 7| . . . . 1 1 3 7 2 1 1 1 1
%e 8| . . . . . 1 2 2 8 4 2 2 1
%e 9| . . . . . 1 1 1 4 9 3 3 1
%e 10| . . . . . . 1 1 2 3 10 5 2
%e 11| . . . . . . 1 1 2 3 5 11 2
%e 12| . . . . . . . 1 1 1 2 2 12
%o (PARI) T(n,k) = for (x=1, oo, if (n\x==k\x, return (n\x)))
%Y Cf. A001651, A213633, A331886.
%K nonn,tabl
%O 0,13
%A _Rémy Sigrist_, Jan 31 2020