A205240 Number of (n+1)X3 0..2 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock differing from the number in each of its horizontal and vertical neighbors

486, 4158, 36478, 323806, 2873148, 25443411, 225349124, 1996606633, 17681948366, 156641245984, 1387300479906, 12289075854961, 108845097936910, 964139798847513, 8539702188030050, 75642295014975612, 669998300863075442

Offset

1,1

Comments

Column 2 of A205246

Links

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

Formula

Empirical: a(n) = 83*a(n-2) +62*a(n-3) -1400*a(n-4) +3028*a(n-5) +15566*a(n-6) -34554*a(n-7) -2930*a(n-8) +172624*a(n-9) +528797*a(n-10) +311184*a(n-11) -2492001*a(n-12) +7439706*a(n-13) +23055160*a(n-14) -17484796*a(n-15) +132409176*a(n-16) -12095322*a(n-17) -302244095*a(n-18) +1672553778*a(n-19) -2384055136*a(n-20) +2362513656*a(n-21) +11058721557*a(n-22) -6140743480*a(n-23) -11862588187*a(n-24) -140351381320*a(n-25) +292423106426*a(n-26) -331440941882*a(n-27) +1143432565197*a(n-28) -1433343509044*a(n-29) +1111337977973*a(n-30) -2097893056546*a(n-31) -1845990127555*a(n-32) +2494742091210*a(n-33) -6613860088532*a(n-34) +12798673882044*a(n-35) -21677389888283*a(n-36) +27817688392656*a(n-37) -45236419184081*a(n-38) +61060473751326*a(n-39) -60450141639301*a(n-40) +103318888641656*a(n-41) -79384721238623*a(n-42) +72193103748248*a(n-43) -62683852343270*a(n-44) +3241028613484*a(n-45) +22465995646013*a(n-46) -75000526328272*a(n-47) +95047402229175*a(n-48) -89667752966740*a(n-49) +93104505619327*a(n-50) -61833805720438*a(n-51) -4148304046392*a(n-52) +34888223414702*a(n-53) -20067567523092*a(n-54) +5612894804612*a(n-55) -5467227940352*a(n-56) -2601758237634*a(n-57) +6380787375141*a(n-58) -556702728328*a(n-59) -1488751940148*a(n-60) -107418263898*a(n-61) +145728484577*a(n-62) +91970842662*a(n-63) -952941688*a(n-64) +1999651744*a(n-65) -2869374919*a(n-66) -426785202*a(n-67) +188074797*a(n-68) -30872712*a(n-69) +3608749*a(n-70) -62574*a(n-71) +62806*a(n-72) +6638*a(n-73) -216*a(n-74) for n>77

Example

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

Crossrefs

Sequence in context: A130181 A158325 A187860 * A206146 A128969 A223412

Adjacent sequences: A205237 A205238 A205239 * A205241 A205242 A205243

Keyword

nonn

Author

R. H. Hardin Jan 24 2012

Status

approved