A280402 Number of 4Xn 0..2 arrays with no element unequal to a strict majority of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

0, 74, 554, 3002, 15476, 78540, 388686, 1909332, 9276316, 44749702, 214274388, 1020029010, 4829443432, 22761611592, 106838241882, 499686947334, 2329557905400, 10829426646892, 50212611191750, 232275648633150

Offset

1,2

Comments

Row 4 of A280398.

Links

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

Formula

Empirical: a(n) = 18*a(n-1) -121*a(n-2) +288*a(n-3) +688*a(n-4) -5964*a(n-5) +12128*a(n-6) +10842*a(n-7) -100332*a(n-8) +176554*a(n-9) +43852*a(n-10) -719126*a(n-11) +1218394*a(n-12) -254764*a(n-13) -2280295*a(n-14) +3640182*a(n-15) -618759*a(n-16) -4365962*a(n-17) +2375176*a(n-18) +10331108*a(n-19) -19520302*a(n-20) +4035478*a(n-21) +31346289*a(n-22) -47846412*a(n-23) +18803646*a(n-24) +23046708*a(n-25) -17099436*a(n-26) -37089846*a(n-27) +57874053*a(n-28) +14706828*a(n-29) -119091345*a(n-30) +143417822*a(n-31) -78450226*a(n-32) +17270732*a(n-33) +7209765*a(n-34) -45937448*a(n-35) +95707480*a(n-36) -110650166*a(n-37) +102265699*a(n-38) -86937826*a(n-39) +25857512*a(n-40) +25153358*a(n-41) -25530212*a(n-42) +45735632*a(n-43) -49720169*a(n-44) +31625612*a(n-45) -30070252*a(n-46) +17623072*a(n-47) -6293712*a(n-48) +3835200*a(n-49) -511808*a(n-50) -77312*a(n-51) -72448*a(n-52) -70656*a(n-53) -9216*a(n-54) for n>59

Example

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

Crossrefs

Cf. A280398.

Sequence in context: A204362 A321114 A205584 * A250913 A186124 A204353

Adjacent sequences: A280399 A280400 A280401 * A280403 A280404 A280405

Keyword

nonn

Author

R. H. Hardin, Jan 02 2017

Status

approved