A196575 Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 1,2,3,0,4 for x=0,1,2,3,4

1, 17, 117, 971, 8781, 63549, 543386, 4387171, 35669727, 291499339, 2369674010, 19309008083, 157281534172, 1280854062374, 10433074844133, 84973377328059, 692089317826577, 5636954496741421, 45911687873344354, 373941550763350063

Offset

1,2

Comments

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

Column 5 of A196578

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = 2*a(n-1) +28*a(n-2) +123*a(n-3) +269*a(n-4) +1189*a(n-5) +3000*a(n-6) +1041*a(n-7) -4132*a(n-8) -12552*a(n-9) -10882*a(n-10) +6150*a(n-11) -21874*a(n-12) -30959*a(n-13) +9437*a(n-14) +12613*a(n-15) +33539*a(n-16) +14333*a(n-17) -23148*a(n-18) +8355*a(n-19) -9358*a(n-20) +3114*a(n-21) -827*a(n-22) +345*a(n-23) +66*a(n-24) -2*a(n-25) +5*a(n-26)

Example

Some solutions for n=4
..0..3..0..0..0....0..3..0..3..0....0..3..0..3..0....0..3..0..0..0
..0..0..2..3..0....0..0..0..0..0....3..0..3..0..0....0..0..3..0..0
..0..0..3..0..3....0..3..2..3..0....0..0..3..0..0....0..0..3..0..0
..0..0..0..3..0....0..0..0..0..0....0..0..0..0..0....0..0..0..3..0

Crossrefs

Sequence in context: A044730 A086020 A056117 * A003109 A066607 A083200

Adjacent sequences: A196572 A196573 A196574 * A196576 A196577 A196578

Keyword

nonn

Author

R. H. Hardin Oct 04 2011

Status

approved