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Rectangular array by antidiagonals: T(n,m) = rank of n*log(2)+m when all the numbers k*log(2)+h, for k >= 1, h >= 0, are jointly ranked.
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%I #6 Oct 06 2017 21:34:46

%S 1,3,2,6,5,4,11,9,8,7,17,15,13,12,10,25,22,20,18,16,14,34,31,28,26,23,

%T 21,19,45,41,38,35,32,29,27,24,57,53,49,46,42,39,36,33,30,70,66,62,58,

%U 54,50,47,43,40,37,85,80,76,72,67,63,59,55,51,48,44,101

%N Rectangular array by antidiagonals: T(n,m) = rank of n*log(2)+m when all the numbers k*log(2)+h, for k >= 1, h >= 0, are jointly ranked.

%C Every positive integer occurs exactly once, so that as a sequence, this is a permutation of the positive integers. As an array, this is the interspersion of 1/log(2); see A283962.

%H Clark Kimberling, <a href="/A293056/b293056.txt">Antidiagonals n=1..60, flattened</a>

%F T(n,m) = Sum_{k=1...n + [m/r]} m+1+[(n-k)r], where r = log(2) and [ ]=floor.

%e Northwest corner:

%e 1 3 6 11 17 25 34

%e 2 5 9 15 22 31 41

%e 4 8 13 20 28 38 49

%e 7 12 18 26 35 46 58

%e 10 16 23 32 42 54 67

%e 14 21 29 39 50 63 77

%e 19 27 36 47 59 73 88

%e 24 33 43 55 68 83 99

%e 30 40 51 64 78 94 111

%e The numbers k*r+h, approximately:

%e (for k=1): 0.693 1.693 2.693 ...

%e (for k=2): 1.386 2.386 3.386 ...

%e (for k=3): 2.079 3.079 4.079 ...

%e Replacing each k*r+h by its rank gives

%e 1 3 6

%e 2 5 9

%e 4 8 13

%t r = Log[2]; z = 12;

%t t[n_, m_] := Sum[Floor[1 + m + (n - k) r], {k, 1, n + Floor[m/r]}];

%t u = Table[t[n, m], {n, 1, z}, {m, 0, z}]

%t Grid[u] (* A293056 array *)

%t Table[t[n - k + 1, k - 1], {n, 1, z}, {k, n, 1, -1}] // Flatten (* A293056 sequence *)

%Y Cf. A283962.

%K nonn,easy,tabl

%O 1,2

%A _Clark Kimberling_, Oct 06 2017