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A236721
Number of (n+1)X(1+1) 0..2 arrays with the maximum plus the upper median plus the lower median minus the minimum of every 2X2 subblock equal
1
81, 211, 550, 1517, 4227, 12072, 34817, 101881, 300694, 896941, 2695583, 8170608, 24926541, 76581709, 236571526, 735006969, 2293934715, 7192276024, 22632537625, 71477629985, 226390525302, 719056784565, 2288987001383, 7302243641824
OFFSET
1,1
COMMENTS
Column 1 of A236728
LINKS
FORMULA
Empirical: a(n) = 7*a(n-1) +12*a(n-2) -177*a(n-3) +89*a(n-4) +1806*a(n-5) -2318*a(n-6) -9698*a(n-7) +16880*a(n-8) +30048*a(n-9) -63832*a(n-10) -54640*a(n-11) +140752*a(n-12) +54864*a(n-13) -184064*a(n-14) -22784*a(n-15) +135936*a(n-16) -4480*a(n-17) -48640*a(n-18) +5120*a(n-19) +5120*a(n-20)
EXAMPLE
Some solutions for n=7
..0..1....0..1....1..1....2..0....1..0....1..0....0..0....0..1....1..0....1..1
..1..2....2..1....0..2....0..2....1..1....2..1....1..2....1..1....2..1....1..2
..2..1....1..2....0..2....1..1....1..0....1..2....0..0....2..1....1..2....0..0
..2..1....2..1....1..1....2..0....0..2....2..1....1..2....1..1....1..2....1..2
..1..2....2..1....2..0....2..0....0..1....2..1....0..0....1..0....1..2....0..0
..1..2....0..1....2..0....1..1....1..1....2..1....2..1....2..0....0..1....2..1
..2..1....1..2....1..1....2..0....0..1....1..2....1..1....0..1....2..1....0..0
..0..1....0..1....2..2....2..0....1..1....0..1....2..1....1..1....0..1....1..2
CROSSREFS
Sequence in context: A236884 A236728 A236877 * A255110 A378789 A062532
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 30 2014
STATUS
approved