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A269040 Number of 6Xn 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once. 1
0, 7128, 67104, 1114848, 14710368, 208867428, 2783857776, 37310632920, 488972134752, 6374741325108, 82212554730696, 1054083281172600, 13425573904100400, 170167484580493980, 2146806101503300608 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 6 of A269035.

LINKS

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

FORMULA

Empirical: a(n) = 12*a(n-1) +182*a(n-2) -1820*a(n-3) -15113*a(n-4) +101664*a(n-5) +646022*a(n-6) -3003324*a(n-7) -15725808*a(n-8) +55305760*a(n-9) +234926070*a(n-10) -698528578*a(n-11) -2270736611*a(n-12) +6320752450*a(n-13) +14600825558*a(n-14) -41434331996*a(n-15) -62768577651*a(n-16) +196263429930*a(n-17) +176943063476*a(n-18) -669462409316*a(n-19) -305019512324*a(n-20) +1647405492614*a(n-21) +230358934675*a(n-22) -2942270801898*a(n-23) +243588718325*a(n-24) +3841770422896*a(n-25) -923967990222*a(n-26) -3689384232910*a(n-27) +1300617284437*a(n-28) +2614259101122*a(n-29) -1127033659748*a(n-30) -1366254718948*a(n-31) +660843537364*a(n-32) +524090586634*a(n-33) -269727615782*a(n-34) -146010681184*a(n-35) +76928224259*a(n-36) +28983533038*a(n-37) -15160113967*a(n-38) -3964319226*a(n-39) +2009807783*a(n-40) +352152984*a(n-41) -170267256*a(n-42) -18138336*a(n-43) +8296524*a(n-44) +408240*a(n-45) -176400*a(n-46) for n>48

EXAMPLE

Some solutions for n=3

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

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

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

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

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

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

CROSSREFS

Cf. A269035.

Sequence in context: A252383 A252350 A251948 * A325066 A100539 A260051

Adjacent sequences:  A269037 A269038 A269039 * A269041 A269042 A269043

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 18 2016

STATUS

approved

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Last modified May 17 20:44 EDT 2021. Contains 343990 sequences. (Running on oeis4.)