A204149 - OEIS

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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

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 A349698

Adjacent sequences: A204146 A204147 A204148 * A204150 A204151 A204152

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 11 2012

STATUS

approved