A184692 1/3 the number of nX7 0..2 arrays with no element equal both to the element above and to the element to its left

729, 786432, 831474432, 878052505824, 927173138866560, 979037502950237760, 1033802803683039013248, 1091631544523681779567680, 1152695101814751026511782496, 1217174425159215145475386956576

Offset

1,1

Comments

Column 7 of A184694

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n)=1373*a(n-1)-382385*a(n-2)+54747930*a(n-3)-5050986386*a(n-4)+332267679041*a(n-5)-16472142082703*a(n-6)+636007583672478*a(n-7)-19508251954601454*a(n-8)+480569383283952657*a(n-9)-9546208348531626993*a(n-10)+152598952268814061851*a(n-11)-1946846244225175080346*a(n-12)+19518911243309328077698*a(n-13)-150002896733353526035184*a(n-14)+849776274453519925228352*a(n-15)-3327166677806732426576264*a(n-16)+7899544532604413646690344*a(n-17)-6508673827964553701633600*a(n-18)-20940104457639861466791296*a(n-19)+72463799516214011378881024*a(n-20)-61429017906552923870936064*a(n-21)-129536619155578798140518400*a(n-22)+380737956559758296779800576*a(n-23)-211491273596407625450717184*a(n-24)-649598231455057371522924544*a(n-25)+1411628961483792374550233088*a(n-26)-535856510128456063711707136*a(n-27)-2479363142583076923579039744*a(n-28)+5970652384046936507902066688*a(n-29)-7499573050858256420655071232*a(n-30)+6280307951272279750928760832*a(n-31)-3675985493399257320121171968*a(n-32)+1481320042982141475269115904*a(n-33)-383743024338594997911683072*a(n-34)+54171200367877184095780864*a(n-35)-2546711369956156422225920*a(n-36)

Example

Some solutions for 3X7 with a(1,1)=0
..0..0..0..1..2..1..0....0..0..0..2..2..2..0....0..0..0..0..2..2..1
..0..1..1..0..2..1..0....0..1..1..0..0..0..1....0..1..1..0..1..2..1
..0..0..0..1..2..2..1....0..0..0..2..2..0..1....0..0..0..1..0..1..2

Crossrefs

Sequence in context: A223793 A223979 A223574 * A272066 A017022 A017106

Adjacent sequences: A184689 A184690 A184691 * A184693 A184694 A184695

Keyword

nonn

Author

R. H. Hardin Jan 20 2011

Status

approved