A240154 Number of 2Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4

3, 5, 8, 19, 36, 57, 120, 218, 377, 758, 1366, 2451, 4815, 8678, 15839, 30594, 55356, 102004, 194522, 353711, 655297, 1238182, 2261878, 4202427, 7889648, 14469040, 26917836, 50315864, 92567160, 172279431, 321102231, 592194036, 1102055156

Offset

1,1

Comments

Row 2 of A240153

Links

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

Formula

Empirical: a(n) = a(n-2) +8*a(n-3) -5*a(n-5) -18*a(n-6) +a(n-7) +10*a(n-8) +16*a(n-9) -5*a(n-10) -10*a(n-11) +a(n-12) +6*a(n-13) -2*a(n-14) -6*a(n-15) -a(n-16) +6*a(n-17) for n>19

Example

Some solutions for n=4
..3..2..3..2....2..2..3..3....3..2..3..3....2..2..3..3....2..2..3..2
..3..2..1..1....0..0..2..1....3..1..2..2....0..2..1..1....0..2..1..1

Crossrefs

Sequence in context: A184434 A196140 A336016 * A376785 A112656 A002366

Adjacent sequences: A240151 A240152 A240153 * A240155 A240156 A240157

Keyword

nonn

Author

R. H. Hardin, Apr 02 2014

Status

approved