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A304665 Number of nX4 0..1 arrays with every element unequal to 0, 1, 3, 5 or 6 king-move adjacent elements, with upper left element zero. 1
5, 21, 30, 93, 249, 544, 1366, 3399, 8219, 20292, 49933, 122347, 301036, 740028, 1817181, 4467409, 10981074, 26981337, 66317395, 163000592, 400583332, 984545201, 2419821691, 5947201372, 14616786659, 35924785775, 88293925192 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A304669.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +14*a(n-3) -22*a(n-4) -3*a(n-5) -75*a(n-6) +93*a(n-7) +26*a(n-8) +215*a(n-9) -225*a(n-10) -93*a(n-11) -431*a(n-12) +399*a(n-13) +190*a(n-14) +679*a(n-15) -477*a(n-16) -271*a(n-17) -784*a(n-18) +455*a(n-19) +378*a(n-20) +790*a(n-21) -394*a(n-22) -421*a(n-23) -734*a(n-24) +146*a(n-25) +319*a(n-26) +472*a(n-27) -66*a(n-28) -251*a(n-29) -323*a(n-30) -245*a(n-31) -18*a(n-32) -128*a(n-33) +134*a(n-34) +128*a(n-35) +176*a(n-36) +40*a(n-37) -55*a(n-38) -63*a(n-39) -10*a(n-40) +6*a(n-41) +6*a(n-42) for n>43

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A304669.

Sequence in context: A186304 A316235 A317156 * A306168 A305645 A316921

Adjacent sequences:  A304662 A304663 A304664 * A304666 A304667 A304668

KEYWORD

nonn

AUTHOR

R. H. Hardin, May 16 2018

STATUS

approved

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Last modified January 20 18:38 EST 2022. Contains 350472 sequences. (Running on oeis4.)