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T(n,k) = number of (n+1) X (k+1) 0..3 arrays x(i,j) with every row sum{j*x(i,j), j=1..k+1} equal, and every column sum{i*x(i,j), i=1..n+1} equal, with top left element <= 1.
4

%I #8 Sep 07 2023 13:51:11

%S 4,4,4,2,16,2,8,19,19,8,10,50,223,50,10,2,124,619,619,124,2,22,575,

%T 523,25138,523,575,22,36,3144,16285,84849,84849,16285,3144,36,2,4295,

%U 141433,150081,21748991,150081,141433,4295,2,94,6598,2231968,32216904,347675392

%N T(n,k) = number of (n+1) X (k+1) 0..3 arrays x(i,j) with every row sum{j*x(i,j), j=1..k+1} equal, and every column sum{i*x(i,j), i=1..n+1} equal, with top left element <= 1.

%H R. H. Hardin, <a href="/A232526/b232526.txt">Table of n, a(n) for n = 1..59</a>

%e Table starts:

%e ..4....4.......2........8........10.........2.......22.........36........2

%e ..4...16......19.......50.......124.......575.....3144.......4295.....6598

%e ..2...19.....223......619.......523.....16285...141433....2231968.20520962

%e ..8...50.....619....25138.....84849....150081.32216904.3452170860

%e .10..124.....523....84849..21748991.347675392

%e ..2..575...16285...150081.347675392

%e .22.3144..141433.32216904

%e .36.4295.2231968

%e ..2.6598

%e .94

%e Some solutions for n=3 and k=4:

%e ..1..3..1..1..2....1..0..2..3..1....0..1..1..0..2....0..2..2..1..2

%e ..2..1..1..3..1....2..1..1..3..1....0..3..3..0..0....1..2..0..1..3

%e ..1..1..3..3..0....1..2..0..1..3....2..1..1..2..0....2..2..2..3..0

%e ..2..2..1..0..3....2..2..3..1..1....1..0..0..1..2....2..1..2..1..2

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_, Nov 25 2013