A205050 Number of (n+1)X4 0..2 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock equal to the number in all its horizontal and vertical neighbors

803, 4171, 23720, 182720, 1280452, 10523741, 76554719, 627391509, 4625078935, 37555149047, 279426142490, 2250418185853, 16869274835868, 134945346237467, 1017754285876347, 8096466609329405, 61370149225028445, 485996587490486860

Offset

1,1

Comments

Column 3 of A205055

Links

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

Formula

Empirical: a(n) = 9*a(n-1) +19*a(n-2) -374*a(n-3) +1554*a(n-4) -3313*a(n-5) +2037*a(n-6) +13607*a(n-7) -59774*a(n-8) +133830*a(n-9) -181169*a(n-10) +85068*a(n-11) +288109*a(n-12) -978591*a(n-13) +1883539*a(n-14) -2936585*a(n-15) +4267787*a(n-16) -5889392*a(n-17) +7243591*a(n-18) -7562613*a(n-19) +7078420*a(n-20) -7501425*a(n-21) +10198666*a(n-22) -13740764*a(n-23) +14894742*a(n-24) -12577898*a(n-25) +8938306*a(n-26) -6164409*a(n-27) +4354773*a(n-28) -2816255*a(n-29) +1501042*a(n-30) -672694*a(n-31) +293114*a(n-32) -135385*a(n-33) +58189*a(n-34) -20496*a(n-35) +6012*a(n-36) -1564*a(n-37) +324*a(n-38) -36*a(n-39) for n>43

Example

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

Crossrefs

Sequence in context: A249007 A249472 A246898 * A202586 A204836 A267932

Adjacent sequences: A205047 A205048 A205049 * A205051 A205052 A205053

Keyword

nonn

Author

R. H. Hardin Jan 21 2012

Status

approved