

A197445


Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,1,0,0 for x=0,1,2,3,4


1



3, 12, 81, 474, 2678, 15410, 88767, 510482, 2936714, 16895217, 97197637, 559175541, 3216923150, 18506887013, 106469709385, 612517802024, 3523801014059, 20272347435052, 116626354899557, 670948774602366, 3859953085161367
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OFFSET

1,1


COMMENTS

Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 3 of A197450


LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200


FORMULA

Empirical: a(n) = 2*a(n1) +12*a(n2) +45*a(n3) +61*a(n4) +20*a(n5) 129*a(n6) 324*a(n7) 344*a(n8) 166*a(n9) +61*a(n10) +268*a(n11) +360*a(n12) +307*a(n13) +240*a(n14) +92*a(n15) 97*a(n16) 142*a(n17) 120*a(n18) 92*a(n19) 32*a(n20) 4*a(n22) for n>25


EXAMPLE

Some solutions for n=4
..1..1..0....1..0..0....0..1..1....0..3..0....0..1..1....0..1..1....1..1..0
..0..0..0....1..3..0....3..0..0....0..0..0....0..3..0....0..0..0....0..0..0
..0..3..1....0..0..1....0..0..0....0..0..3....0..0..0....3..0..1....0..0..0
..0..0..1....0..0..1....0..1..1....0..0..0....0..0..0....0..0..1....0..3..0


CROSSREFS

Sequence in context: A303227 A182166 A303047 * A303033 A207322 A188227
Adjacent sequences: A197442 A197443 A197444 * A197446 A197447 A197448


KEYWORD

nonn


AUTHOR

R. H. Hardin Oct 15 2011


STATUS

approved



