A196860 - OEIS

A196860

Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,4,2,0,1 for x=0,1,2,3,4

1, 6, 26, 102, 473, 1900, 7428, 29859, 120761, 488123, 1973886, 7978980, 32236748, 130244330, 526284444, 2126673912, 8593813805, 34727312754, 140331197760, 567069475233, 2291493536866, 9259796163176, 37418329505296, 151205438122194

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OFFSET

1,2

COMMENTS

Every 0 is next to 0 3's, every 1 is next to 1 4's, every 2 is next to 2 2's, every 3 is next to 3 0's, every 4 is next to 4 1's

Column 5 of A196863

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) -7*a(n-2) +18*a(n-3) -25*a(n-4) +26*a(n-5) -19*a(n-6) -66*a(n-7) -152*a(n-8) -371*a(n-9) -310*a(n-10) -216*a(n-11) +559*a(n-12) +809*a(n-13) +807*a(n-14) -43*a(n-15) +155*a(n-16) +1212*a(n-17) +1159*a(n-18) -383*a(n-19) -1650*a(n-20) -916*a(n-21) +491*a(n-22) +768*a(n-23) +310*a(n-24) -217*a(n-25) -227*a(n-26) -31*a(n-27) +40*a(n-28) +30*a(n-29) +2*a(n-30) -5*a(n-31)

EXAMPLE

Some solutions for n=4

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

..0..0..1..4..1....0..1..0..0..0....2..2..0..2..2....2..2..2..0..2

..2..2..0..1..0....1..4..1..0..0....2..2..0..2..2....2..0..0..2..2

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

CROSSREFS

Sequence in context: A307306 A143955 A256428 * A254317 A037545 A371438

Adjacent sequences: A196857 A196858 A196859 * A196861 A196862 A196863

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 06 2011

STATUS

approved