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A300461 Number of nX4 0..1 arrays with every element equal to 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
0, 4, 8, 28, 142, 540, 2585, 11343, 51501, 233028, 1052448, 4769842, 21579345, 97715668, 442378911, 2002838338, 9067930634, 41054700887, 185876096558, 841553822832, 3810142997823, 17250454214015, 78101569076062 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 4 of A300465.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +6*a(n-2) -5*a(n-3) -37*a(n-4) -59*a(n-5) -39*a(n-6) +80*a(n-7) -279*a(n-8) +328*a(n-9) +1083*a(n-10) -25*a(n-11) +6234*a(n-12) +6280*a(n-13) -5927*a(n-14) +13954*a(n-15) -677*a(n-16) -53183*a(n-17) +32616*a(n-18) -49693*a(n-19) -57573*a(n-20) +142653*a(n-21) -126299*a(n-22) +100762*a(n-23) +71676*a(n-24) -234851*a(n-25) +178322*a(n-26) -92379*a(n-27) -11243*a(n-28) +181969*a(n-29) -91225*a(n-30) +44201*a(n-31) -9047*a(n-32) -83657*a(n-33) +21643*a(n-34) +39079*a(n-35) -7039*a(n-36) -11806*a(n-37) +2726*a(n-38) +9392*a(n-39) -18923*a(n-40) +27265*a(n-41) -28247*a(n-42) +17148*a(n-43) -7200*a(n-44) +2338*a(n-45) +517*a(n-46) -867*a(n-47) -170*a(n-48) +576*a(n-49) -297*a(n-50) +60*a(n-51) -4*a(n-52) for n>54

EXAMPLE

Some solutions for n=5

..0..0..1..1. .0..0..0..0. .0..0..0..0. .0..0..1..1. .0..0..0..1

..0..0..1..1. .0..1..0..0. .0..1..1..0. .0..1..1..0. .0..0..1..1

..0..1..0..0. .1..1..1..1. .1..1..0..0. .0..0..0..0. .0..1..1..1

..1..0..0..1. .1..0..0..1. .1..0..0..1. .0..1..1..1. .0..0..0..0

..1..1..1..1. .0..0..1..1. .1..1..1..1. .1..1..1..1. .0..0..0..0

CROSSREFS

Cf. A300465.

Sequence in context: A143555 A025234 A075308 * A280085 A322784 A297638

Adjacent sequences:  A300458 A300459 A300460 * A300462 A300463 A300464

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 06 2018

STATUS

approved

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Last modified July 16 11:09 EDT 2020. Contains 335784 sequences. (Running on oeis4.)