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A267669
Number of 4Xn 0..1 arrays with every repeated value in every row unequal to the previous repeated value, and in every column equal to the previous repeated value, and new values introduced in row-major sequential order.
1
7, 98, 453, 3143, 10933, 60401, 188301, 951113, 2812057, 13690793, 39294261, 188823533, 531699829, 2551208657, 7083277713, 34139004377, 93677247421, 454955695853, 1235099875965, 6055154070065, 16269918251065, 80602553434841
OFFSET
1,1
COMMENTS
Row 4 of A267667.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) +46*a(n-2) -255*a(n-3) -804*a(n-4) +5287*a(n-5) +6393*a(n-6) -57990*a(n-7) -17379*a(n-8) +368289*a(n-9) -70362*a(n-10) -1394997*a(n-11) +645844*a(n-12) +3138583*a(n-13) -1858369*a(n-14) -4077534*a(n-15) +2440404*a(n-16) +2940332*a(n-17) -1387260*a(n-18) -1138872*a(n-19) +275184*a(n-20) +183456*a(n-21)
EXAMPLE
Some solutions for n=7
..0..1..0..0..1..0..1....0..1..0..1..1..0..0....0..0..1..0..1..0..1
..0..0..1..0..1..1..0....0..0..1..0..1..0..1....0..1..0..1..1..0..0
..1..0..1..0..1..0..1....0..1..0..1..1..0..0....1..0..1..0..1..0..0
..0..1..1..0..1..0..0....0..1..1..0..0..1..0....0..0..1..0..1..0..1
CROSSREFS
Cf. A267667.
Sequence in context: A022008 A200504 A267641 * A288681 A124092 A036293
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 19 2016
STATUS
approved