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 A269280 Number of 5Xn 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once. 1
 0, 236196, 36673560, 4684312584, 542973139128, 59587625651904, 6310088238337128, 651615466055490216, 66042694681962193944, 6597498728751383594736, 651529527626284234223688 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row 5 of A269276. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 262*a(n-1) -25913*a(n-2) +1271424*a(n-3) -36373480*a(n-4) +662028380*a(n-5) -8018113210*a(n-6) +65608158980*a(n-7) -356568260410*a(n-8) +1185405035940*a(n-9) -1609856308508*a(n-10) -4162483461884*a(n-11) +23709461283851*a(n-12) -40474763971218*a(n-13) +272846513475*a(n-14) +106799477038956*a(n-15) -171480164894532*a(n-16) +115612142099328*a(n-17) -29562621871104*a(n-18) for n>23 EXAMPLE Some solutions for n=2 ..1..0. .1..1. .0..0. .0..1. .1..1. .0..2. .0..1. .1..1. .0..2. .0..1 ..0..3. .0..1. .1..0. .2..0. .1..1. .1..1. .0..0. .0..1. .3..2. .3..2 ..1..3. .1..1. .1..3. .2..2. .1..0. .3..2. .0..0. .2..2. .2..3. .1..0 ..3..3. .2..0. .2..1. .3..1. .2..0. .3..3. .2..2. .0..2. .1..0. .1..1 ..1..0. .0..2. .0..0. .0..2. .2..1. .1..3. .1..0. .3..1. .3..2. .1..3 CROSSREFS Cf. A269276. Sequence in context: A254264 A254257 A254303 * A092009 A160920 A235105 Adjacent sequences:  A269277 A269278 A269279 * A269281 A269282 A269283 KEYWORD nonn AUTHOR R. H. Hardin, Feb 21 2016 STATUS approved

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Last modified December 8 17:01 EST 2021. Contains 349596 sequences. (Running on oeis4.)