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A204149 Number of (n+2)X6 0..2 arrays with every 3X3 subblock having equal diagonal elements or equal antidiagonal elements, and new values 0..2 introduced in row major order 1
127022, 891662, 4683434, 26497814, 146747822, 826613438, 4577683574, 25733247662, 142927791734, 798288202838, 4439968756022, 24804328388438, 138111783343814, 770766788584982, 4295189965272374, 23962592671777622 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A204153

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +9*a(n-2) -16*a(n-3) +162*a(n-4) -680*a(n-5) +1316*a(n-6) +3646*a(n-7) -11416*a(n-8) -45560*a(n-9) +55336*a(n-10) -404680*a(n-11) -687384*a(n-12) +2793136*a(n-13) +5954432*a(n-14) -7133728*a(n-15) +26057024*a(n-16) +51024800*a(n-17) -122086400*a(n-18) -7443200*a(n-19) -170156800*a(n-20) -1801072000*a(n-21) -482608000*a(n-22) +6153120000*a(n-23) -3596160000*a(n-24) +9433600000*a(n-25) -1420800000*a(n-26) +6016000000*a(n-27) -39680000000*a(n-28) +25600000000*a(n-29) for n>30

EXAMPLE

Some solutions for n=4

..0..1..1..0..0..2....0..1..2..1..2..0....0..0..1..0..1..0....0..0..0..1..1..0

..0..1..0..0..0..0....1..0..1..2..0..2....2..0..0..1..0..2....1..0..0..0..0..1

..1..0..0..0..0..0....1..1..0..0..2..0....1..0..0..0..1..2....1..1..0..0..0..1

..1..0..0..0..0..1....1..1..0..0..0..2....0..0..0..0..0..1....1..1..1..0..0..0

..0..0..0..0..1..1....2..0..1..0..0..1....0..0..0..0..0..0....2..1..1..1..0..0

..0..0..0..1..2..2....0..1..1..1..0..0....2..2..0..0..1..0....1..0..2..1..1..0

CROSSREFS

Sequence in context: A251016 A349284 A251027 * A066690 A189185 A234978

Adjacent sequences:  A204146 A204147 A204148 * A204150 A204151 A204152

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 11 2012

STATUS

approved

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Last modified December 8 17:01 EST 2021. Contains 349596 sequences. (Running on oeis4.)