A240272 Number of 2Xn 0..3 arrays with no element equal to zero 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, modulo 4

3, 7, 35, 157, 713, 3263, 14895, 68101, 311509, 1424689, 6516312, 29807450, 136351053, 623728103, 2853225545, 13052077767, 59706884718, 273130241113, 1249440509707, 5715597380517, 26146153523610, 119606300969406

Offset

1,1

Comments

Row 2 of A240271

Links

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

Formula

Empirical: a(n) = 8*a(n-1) -20*a(n-2) +34*a(n-3) -84*a(n-4) +92*a(n-5) -68*a(n-6) +222*a(n-7) +13*a(n-8) -251*a(n-9) +25*a(n-10) -495*a(n-11) +485*a(n-12) -44*a(n-13) -180*a(n-14) +554*a(n-15) -648*a(n-16) +14*a(n-17) +152*a(n-18) -190*a(n-19) -140*a(n-20) +397*a(n-21) -273*a(n-22) +75*a(n-23) +167*a(n-24) -136*a(n-25) +27*a(n-26) for n>28

Example

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

Crossrefs

Sequence in context: A055487 A121130 A006099 * A053530 A215575 A266049

Adjacent sequences: A240269 A240270 A240271 * A240273 A240274 A240275

Keyword

nonn

Author

R. H. Hardin, Apr 03 2014

Status

approved