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A274732 Number of 7Xn 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) or (-1,0) and new values introduced in order 0..2. 1
32, 1296, 16524, 301784, 5634776, 105328812, 1980677448, 37188898120, 699226867860, 13139454740876, 246989200003420, 4642070954166124, 87252983103535936, 1639953977382243676, 30824192792654598004 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 7 of A274728.

LINKS

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

FORMULA

Empirical: a(n) = 21*a(n-1) +46*a(n-2) -2078*a(n-3) +7099*a(n-4) +30390*a(n-5) -199330*a(n-6) +32493*a(n-7) +1799239*a(n-8) -2883655*a(n-9) -6458651*a(n-10) +19972172*a(n-11) +4488011*a(n-12) -63185111*a(n-13) +38593516*a(n-14) +97573203*a(n-15) -147528893*a(n-16) +26937123*a(n-17) +105357461*a(n-18) -172813699*a(n-19) +142443589*a(n-20) +18232365*a(n-21) -135277945*a(n-22) +91577781*a(n-23) -13939351*a(n-24) -6667960*a(n-25) +1422372*a(n-26) +709307*a(n-27) -229702*a(n-28) +8892*a(n-29) +1296*a(n-30) for n>34

EXAMPLE

Some solutions for n=3

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

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

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

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

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

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

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

CROSSREFS

Cf. A274728.

Sequence in context: A278704 A275141 A275036 * A241800 A231040 A254152

Adjacent sequences:  A274729 A274730 A274731 * A274733 A274734 A274735

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 03 2016

STATUS

approved

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Last modified December 5 11:43 EST 2021. Contains 349557 sequences. (Running on oeis4.)