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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 1
8, 128, 231, 883, 3716, 15780, 67169, 286470, 1221769, 5217560, 22265850, 95057632, 405842314, 1732540170, 7396709713, 31579033671, 134818081160, 575577552695, 2457313356354, 10490943349879, 44788864504224, 191216664019901 (list; graph; refs; listen; history; text; internal format)
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: A171755 A338808 A233089 * A093586 A238651 A291849

Adjacent sequences:  A204191 A204192 A204193 * A204195 A204196 A204197

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 12 2012

STATUS

approved

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Last modified December 2 19:48 EST 2021. Contains 349445 sequences. (Running on oeis4.)