A204194 Number of nX5 0..1 arrays with no occurrence of three equal elements in a row horizontally, vertically or nw-to-se diagonally, and new values 0..1 introduced in row major order

8, 128, 231, 883, 3716, 15780, 67169, 286470, 1221769, 5217560, 22265850, 95057632, 405842314, 1732540170, 7396709713, 31579033671, 134818081160, 575577552695, 2457313356354, 10490943349879, 44788864504224, 191216664019901

Offset

1,1

Comments

Column 5 of A204197

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +15*a(n-2) +9*a(n-3) -118*a(n-4) -238*a(n-5) +472*a(n-6) +1447*a(n-7) -1075*a(n-8) -4741*a(n-9) +1560*a(n-10) +9731*a(n-11) -1462*a(n-12) -13452*a(n-13) +1230*a(n-14) +12863*a(n-15) -1868*a(n-16) -8177*a(n-17) +3206*a(n-18) +2964*a(n-19) -3943*a(n-20) -99*a(n-21) +3247*a(n-22) -480*a(n-23) -1779*a(n-24) +260*a(n-25) +634*a(n-26) -75*a(n-27) -141*a(n-28) +13*a(n-29) +18*a(n-30) -a(n-31) -a(n-32) for n>35

Example

Some solutions for n=5
..0..0..1..1..0....0..0..1..0..1....0..0..1..0..0....0..0..1..0..0
..0..1..0..0..1....0..1..1..0..1....1..1..0..1..1....0..1..0..0..1
..1..1..0..1..1....1..1..0..1..0....1..0..1..1..0....1..1..0..1..1
..1..0..1..1..0....0..0..1..0..0....0..0..1..0..1....1..0..1..0..0
..0..1..0..0..1....0..0..1..0..1....0..1..0..1..1....0..0..1..0..1

Crossrefs

Sequence in context: A338808 A363330 A233089 * A093586 A238651 A291849

Adjacent sequences: A204191 A204192 A204193 * A204195 A204196 A204197

Keyword

nonn

Author

R. H. Hardin Jan 12 2012

Status

approved