A280120 Number of nX4 0..2 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

2, 28, 168, 1030, 5802, 31608, 171100, 916768, 4882310, 25849910, 136148532, 713757316, 3726366076, 19383636846, 100497836596, 519525218302, 2678590148146, 13777413523624, 70710464750916, 362190825607320

Offset

1,1

Comments

Column 4 of A280124.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 6*a(n-1) +25*a(n-2) -148*a(n-3) -307*a(n-4) +1228*a(n-5) +2475*a(n-6) -3210*a(n-7) -14762*a(n-8) -9146*a(n-9) +59251*a(n-10) +78496*a(n-11) -107489*a(n-12) -241242*a(n-13) -88943*a(n-14) +526534*a(n-15) +556734*a(n-16) -621460*a(n-17) -529201*a(n-18) -198256*a(n-19) -192232*a(n-20) +1078880*a(n-21) +376432*a(n-22) -508032*a(n-23) +30976*a(n-24) -331776*a(n-25) -28672*a(n-26) +229376*a(n-27) -65536*a(n-28) for n>34

Example

Some solutions for n=4
..0..0..1..1. .0..1..1..1. .0..1..1..1. .0..0..0..0. .0..0..1..1
..0..0..1..0. .0..0..1..1. .0..1..1..1. .1..0..0..0. .0..1..1..1
..0..0..0..0. .0..0..0..1. .1..1..1..0. .2..2..0..0. .0..1..1..1
..0..0..0..0. .0..0..0..1. .1..1..0..0. .2..2..0..0. .0..1..1..1

Crossrefs

Cf. A280124.

Sequence in context: A338426 A347602 A006332 * A065340 A001798 A123787

Adjacent sequences: A280117 A280118 A280119 * A280121 A280122 A280123

Keyword

nonn

Author

R. H. Hardin, Dec 26 2016

Status

approved