OFFSET
1,1
COMMENTS
Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 3's, every 4 is next to 4 4's
Column 6 of A196436
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 3*a(n-1) +25*a(n-2) +133*a(n-3) +160*a(n-4) -228*a(n-5) -4347*a(n-6) -6390*a(n-7) +22042*a(n-8) +69473*a(n-9) -121351*a(n-10) -166866*a(n-11) +99488*a(n-12) +403431*a(n-13) +573755*a(n-14) -459164*a(n-15) -3331885*a(n-16) +882345*a(n-17) +10267362*a(n-18) -10417263*a(n-19) +1297172*a(n-20) -12680768*a(n-21) +28807056*a(n-22) +10288169*a(n-23) -42690735*a(n-24) -80670630*a(n-25) +131547842*a(n-26) +171329522*a(n-27) -592636916*a(n-28) +854087725*a(n-29) -1000480787*a(n-30) +1181403998*a(n-31) -1469943639*a(n-32) +1174515719*a(n-33) -815203545*a(n-34) +676224576*a(n-35) -204277861*a(n-36) +154628965*a(n-37) -31210484*a(n-38) -83098378*a(n-39) +84233332*a(n-40) +75103457*a(n-41) +28535852*a(n-42) +26793544*a(n-43) -25032839*a(n-44) +14612191*a(n-45) +3404438*a(n-46) +11277482*a(n-47) +4472344*a(n-48) +4553725*a(n-49) -8053851*a(n-50) +5355502*a(n-51) -5356445*a(n-52) +3186418*a(n-53) -4432672*a(n-54) +84462*a(n-55) -1407676*a(n-56) +477617*a(n-57) +72338*a(n-58) +149289*a(n-59) -20471*a(n-60) -2699*a(n-61) -5568*a(n-62) +587*a(n-63) +504*a(n-64) +283*a(n-65) -29*a(n-66) -27*a(n-67) -4*a(n-68) +a(n-69)
EXAMPLE
Some solutions for n=4
..0..0..0..0..1..0....0..0..0..1..1..0....0..0..0..0..1..1....0..1..0..0..1..1
..1..1..0..0..1..0....0..0..0..0..0..0....0..0..1..0..0..0....0..1..0..1..0..0
..0..0..0..0..0..0....1..0..1..0..0..1....0..0..1..0..1..0....0..0..0..1..0..0
..0..0..1..1..0..0....1..0..1..0..0..1....0..0..0..0..1..0....0..0..0..0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 02 2011
STATUS
approved