OFFSET
1,2
COMMENTS
Every 0 is next to 0 4's, every 1 is next to 1 3's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 2's
Column 5 of A196904
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 6*a(n-1) +76*a(n-2) +73*a(n-3) +327*a(n-4) -8263*a(n-5) -71625*a(n-6) +175433*a(n-7) +1063320*a(n-8) -1808685*a(n-9) +734623*a(n-10) +8092720*a(n-11) -112351825*a(n-12) -130718118*a(n-13) +1230059528*a(n-14) +1460469462*a(n-15) -9786568154*a(n-16) +1022719195*a(n-17) +49177537682*a(n-18) -65134988420*a(n-19) -130371414683*a(n-20) +346736287590*a(n-21) +119242012070*a(n-22) -1298970832063*a(n-23) +533019336684*a(n-24) +4407103350916*a(n-25) -2990704397439*a(n-26) -11508938420513*a(n-27) +5847585456801*a(n-28) +23573141862420*a(n-29) -6899344093121*a(n-30) -37396424606024*a(n-31) +25867286046675*a(n-32) +42466577181838*a(n-33) -57652388028834*a(n-34) -63073474370951*a(n-35) +13966711599770*a(n-36) +113260412308308*a(n-37) +89777154961811*a(n-38) -81535789874363*a(n-39) -124455352601926*a(n-40) -9282468293623*a(n-41) +68580077552679*a(n-42) +38892855908975*a(n-43) -6027900563533*a(n-44) -79220468099273*a(n-45) +9564883542984*a(n-46) +85061666448553*a(n-47) +16658468911308*a(n-48) -57707114922236*a(n-49) -38638651615232*a(n-50) +31746894661990*a(n-51) +19931143783057*a(n-52) -8947763153899*a(n-53) -6360567128345*a(n-54) +700757965928*a(n-55) +2311545820475*a(n-56) +1040601243*a(n-57) -585167189225*a(n-58) -6960399069*a(n-59) +91521709619*a(n-60) +2641361941*a(n-61) -10609685670*a(n-62) -269891645*a(n-63) +982868996*a(n-64) +33565862*a(n-65) -67682410*a(n-66) -4833950*a(n-67) +3248340*a(n-68) +173544*a(n-69) -75920*a(n-70) +64*a(n-71) +384*a(n-72)
EXAMPLE
Some solutions for n=4
..0..0..0..3..0....0..1..0..3..0....0..0..3..0..0....0..3..0..3..0
..3..0..0..0..0....0..3..0..0..3....0..3..0..1..0....3..0..0..0..0
..0..3..1..0..0....3..0..0..3..0....0..1..0..3..0....0..0..0..3..1
..0..0..0..3..0....0..3..0..1..0....0..0..3..0..0....0..0..0..0..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 07 2011
STATUS
approved