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A220553 T(n,k)=Number of ways to reciprocally link elements of an nXk array either to themselves or to exactly one horizontal, vertical or antidiagonal neighbor 8

%I

%S 1,2,2,3,8,3,5,29,29,5,8,108,224,108,8,13,401,1814,1814,401,13,21,

%T 1490,14556,32173,14556,1490,21,34,5536,117022,565061,565061,117022,

%U 5536,34,55,20569,940432,9943416,21668208,9943416,940432,20569,55,89,76424

%N T(n,k)=Number of ways to reciprocally link elements of an nXk array either to themselves or to exactly one horizontal, vertical or antidiagonal neighbor

%C Table starts

%C ...1.......2...........3...............5...................8

%C ...2.......8..........29.............108.................401

%C ...3......29.........224............1814...............14556

%C ...5.....108........1814...........32173..............565061

%C ...8.....401.......14556..........565061............21668208

%C ..13....1490......117022.........9943416...........832899775

%C ..21....5536......940432.......174911750.........32001129185

%C ..34...20569.....7558245......3077034244.......1229633337183

%C ..55...76424....60744605.....54130248568......47247493674864

%C ..89..283953...488197825....952245176313....1815445803499208

%C .144.1055026..3923590632..16751640356635...69756959373004005

%C .233.3919944.31533457665.294690365449276.2680352078247056300

%H R. H. Hardin, <a href="/A220553/b220553.txt">Table of n, a(n) for n = 1..312</a>

%e Some solutions for n=3 k=4 0=self 2=n 3=ne 4=w 6=e 7=sw 8=s (reciprocal directions total 10)

%e ..8..8..0..7....0..6..4..0....0..0..6..4....6..4..7..0....0..0..0..0

%e ..2..2..3..0....0..7..0..7....0..0..6..4....0..3..8..0....8..0..0..8

%e ..0..0..6..4....3..0..3..0....0..0..6..4....0..0..2..0....2..6..4..2

%Y Column 1 is A000045(n+1)

%K nonn,tabl

%O 1,2

%A _R. H. Hardin_ Dec 15 2012

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Last modified October 19 22:00 EDT 2021. Contains 348095 sequences. (Running on oeis4.)