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A232945
Number of nX5 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, vertically or antidiagonally, and top left element zero
2
81, 3363, 161621, 7915555, 389997789, 19245039957, 950054488141, 46905123394619, 2315805078150557, 114336803085406731, 5645086862993222953, 278711788919053258129, 13760685779790427073277, 679398875935060965853215
OFFSET
1,1
COMMENTS
Column 5 of A232948
LINKS
FORMULA
Empirical: a(n) = 67*a(n-1) -957*a(n-2) +4487*a(n-3) -10440*a(n-4) +9842*a(n-5) +34671*a(n-6) -145789*a(n-7) +111684*a(n-8) +296032*a(n-9) -481473*a(n-10) -167907*a(n-11) +608240*a(n-12) -12730*a(n-13) -416027*a(n-14) +59065*a(n-15) +178117*a(n-16) -40627*a(n-17) -41054*a(n-18) +13432*a(n-19) +2184*a(n-20) -816*a(n-21) for n>23
EXAMPLE
Some solutions for n=3
..0..2..0..0..2....0..0..2..0..2....0..2..2..2..2....0..0..1..1..0
..2..2..2..0..0....2..2..0..2..3....2..0..0..2..0....1..0..1..0..1
..3..2..0..0..1....0..0..0..2..3....0..2..0..0..1....1..1..1..0..1
CROSSREFS
Sequence in context: A205207 A254415 A017744 * A345005 A223477 A237842
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 02 2013
STATUS
approved