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A220624 Number of ways to reciprocally link elements of an 5Xn array either to themselves or to exactly one horizontal, diagonal and antidiagonal neighbor 1
1, 228, 4657, 243119, 8608738, 356768525, 13864972277, 553125347136, 21831846871613, 865461975018339, 34247958158855874, 1356237159188241529, 53691862459540232153, 2125854494007156918632, 84166119627538600335289 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 5 of A220621

LINKS

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

FORMULA

Empirical: a(n) = 29*a(n-1) +557*a(n-2) -4948*a(n-3) -24662*a(n-4) +187560*a(n-5) +182180*a(n-6) -1893504*a(n-7) -127344*a(n-8) +6325072*a(n-9) +132352*a(n-10) -7384448*a(n-11) -1323456*a(n-12) +2439808*a(n-13) +987648*a(n-14) -7168*a(n-15) -69632*a(n-16) +32768*a(n-17)

EXAMPLE

Some solutions for n=3 0=self 1=nw 3=ne 4=w 6=e 7=sw 9=se (reciprocal directions total 10)

..9..0..0....0..7..0....6..4..0....0..7..0....0..6..4....0..0..7....0..6..4

..0..1..0....3..7..0....0..0..0....3..7..0....0..9..0....0..3..0....0..7..0

..6..4..7....3..6..4....0..6..4....3..6..4....0..0..1....0..9..0....3..7..0

..9..3..0....0..7..7....0..6..4....6..4..0....6..4..0....6..4..1....3..0..0

..0..1..0....3..3..0....0..6..4....6..4..0....0..0..0....0..6..4....6..4..0

CROSSREFS

Sequence in context: A302755 A064245 A201238 * A098246 A091551 A033528

Adjacent sequences:  A220621 A220622 A220623 * A220625 A220626 A220627

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 17 2012

STATUS

approved

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Last modified June 27 04:37 EDT 2022. Contains 354888 sequences. (Running on oeis4.)