A240462 Number of 3Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or three plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest, modulo 4.
12, 102, 874, 7589, 65723, 568370, 4916340, 42530527, 367908385, 3182471383, 27528807013, 238127592175, 2059829147851, 17817722472564, 154124971684131, 1333195242928609, 11532260863126369, 99755106819505532, 862890740313446216
Offset: 1
Keywords
Examples
Some solutions for n=4 ..2..2..0..2....0..0..2..2....2..2..2..2....2..0..2..0....0..2..0..2 ..0..0..0..0....0..2..0..2....0..0..0..2....0..0..0..2....0..3..1..3 ..0..0..2..0....2..2..2..2....3..2..0..1....0..0..0..0....2..2..3..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = 18*a(n-1) -105*a(n-2) +200*a(n-3) +242*a(n-4) -2119*a(n-5) +7083*a(n-6) -9004*a(n-7) -24192*a(n-8) +72426*a(n-9) -3118*a(n-10) -103236*a(n-11) -4239*a(n-12) +64281*a(n-13) +119026*a(n-14) -161710*a(n-15) +142844*a(n-16) -25892*a(n-17) -337024*a(n-18) +223288*a(n-19) +175280*a(n-20) -145120*a(n-21) -22528*a(n-22) +23040*a(n-23)
Comments