A196920 Number of nX6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 1,3,2,4,0 for x=0,1,2,3,4

1, 9, 58, 335, 2659, 18354, 123261, 841565, 5796373, 40206133, 280010220, 1953475131, 13643051451, 95356664458, 666849653893, 4665205889379, 32645573075339, 228480724683384, 1599269236394946, 11195004310971415

Offset

1,2

Comments

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

Column 6 of A196922

Links

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

Formula

Empirical: a(n) = 11*a(n-1) -30*a(n-2) +34*a(n-3) -174*a(n-4) +374*a(n-5) -645*a(n-6) -1568*a(n-7) -3864*a(n-8) -2737*a(n-9) +19896*a(n-10) +39789*a(n-11) +53807*a(n-12) -25645*a(n-13) -97487*a(n-14) -31786*a(n-15) +356123*a(n-16) +927682*a(n-17) +716971*a(n-18) -1120870*a(n-19) -3680755*a(n-20) -3507819*a(n-21) +1342053*a(n-22) +7156543*a(n-23) +6759831*a(n-24) -751579*a(n-25) -7948456*a(n-26) -7605926*a(n-27) -1091182*a(n-28) +4551985*a(n-29) +4822652*a(n-30) +1470465*a(n-31) -1156354*a(n-32) -1454677*a(n-33) -488873*a(n-34) +58506*a(n-35) +204668*a(n-36) +24265*a(n-37) +17367*a(n-38) +2506*a(n-39) +1238*a(n-40) +3804*a(n-41) -6754*a(n-42) +876*a(n-43) -504*a(n-44) +432*a(n-45) for n>46

Example

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

Crossrefs

Sequence in context: A009034 A026377 A016209 * A129173 A271271 A055423

Adjacent sequences: A196917 A196918 A196919 * A196921 A196922 A196923

Keyword

nonn

Author

R. H. Hardin Oct 07 2011

Status

approved