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A240480 Number of nX4 0..1 arrays with no element equal to more than two horizontal or vertical neighbors, with new values 0..1 introduced in row major order 1
8, 81, 578, 4104, 29084, 205754, 1455916, 10304849, 72937769, 516249590, 3653997013, 25862854244, 183056241833, 1295664762145, 9170663523390, 64909590438320, 459427491120642, 3251809452014192, 23016177558642426 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A240484

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) +2*a(n-2) -7*a(n-3) -25*a(n-4) -6*a(n-5) +150*a(n-6) +12*a(n-7) -456*a(n-8) -134*a(n-9) +408*a(n-10) +116*a(n-11) -171*a(n-12) +73*a(n-13) +388*a(n-14) +87*a(n-15) -127*a(n-16) -168*a(n-17) -62*a(n-18) -12*a(n-19) +16*a(n-20) +8*a(n-21) +2*a(n-22)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A027768 A236749 A343274 * A274752 A240632 A007792

Adjacent sequences:  A240477 A240478 A240479 * A240481 A240482 A240483

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 06 2014

STATUS

approved

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Last modified October 4 08:15 EDT 2022. Contains 357238 sequences. (Running on oeis4.)