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%I #5 Mar 31 2012 12:37:34
%S 4,15,15,53,176,53,170,1533,1533,170,497,8824,21379,8824,497,1407,
%T 40038,142627,142627,40038,1407,3962,167910,748627,1115472,748627,
%U 167910,3962,10867,710895,3846906,8039420,8039420,3846906,710895,10867,30956,3139374
%N T(n,k)=Number of nXk 1..4 arrays with no element with value z exactly a city block distance of z from another element with value z
%C Table starts
%C .....4......15........53.........170..........497..........1407..........3962
%C ....15.....176......1533........8824........40038........167910........710895
%C ....53....1533.....21379......142627.......748627.......3846906......23759000
%C ...170....8824....142627.....1115472......8039420......69751928.....890122678
%C ...497...40038....748627.....8039420.....98861559....1663213556...37591420090
%C ..1407..167910...3846906....69751928...1663213556...51104966068.1928958791380
%C ..3962..710895..23759000...890122678..37591420090.1928958791380
%C .10867.3139374.197838865.13542249784.889827826226
%H R. H. Hardin, <a href="/A210788/b210788.txt">Table of n, a(n) for n = 1..84</a>
%e Some solutions for n=4 k=3
%e ..1..2..2....2..3..4....2..4..4....1..3..1....4..2..4....1..4..4....2..2..1
%e ..3..1..4....3..4..2....2..3..4....4..1..2....4..4..3....2..2..4....1..3..3
%e ..4..3..4....1..3..4....3..4..2....4..3..2....2..3..1....3..3..3....4..3..2
%e ..1..2..3....4..1..3....1..3..1....1..4..3....3..1..2....1..3..2....2..1..4
%K nonn,tabl
%O 1,1
%A _R. H. Hardin_ Mar 26 2012