A187641 Number of (n+2)X4 0..2 arrays with each 3X3 subblock having sum 9

17701, 79259, 363533, 1747075, 9368309, 51019403, 283738813, 1661843915, 9825500309, 58770460003, 361966285061, 2243939191979, 14018792443981, 89240424327899, 570881059653413, 3672734493171955, 23937367270575029

Offset

1,1

Comments

Column 2 of A187645

Links

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

Formula

Empirical: a(n)=10*a(n-1)-21*a(n-2)+1179*a(n-3)-11790*a(n-4)+24759*a(n-5)-617826*a(n-6)+6178260*a(n-7)-12974346*a(n-8)+191371452*a(n-9)-1913714520*a(n-10)+4018800492*a(n-11)-39296551266*a(n-12)+392965512660*a(n-13)-825227576586*a(n-14)+5685269974278*a(n-15)-56852699742780*a(n-16)+119390669459838*a(n-17)-601117515776444*a(n-18)+6011175157764440*a(n-19)-12623467831305324*a(n-20)+47542191308281032*a(n-21)-475421913082810320*a(n-22)+998386017473901672*a(n-23)-2854901415527246781*a(n-24)+28549014155272467810*a(n-25)-59952929726072182401*a(n-26)+131363016062080959063*a(n-27)-1313630160620809590630*a(n-28)+2758623337303700140323*a(n-29)-4653876942691669277370*a(n-30)+46538769426916692773700*a(n-31)-97731415796525054824770*a(n-32)+127104364341223563535956*a(n-33)-1271043643412235635359560*a(n-34)+2669191651165694834255076*a(n-35)-2671034245317344639898792*a(n-36)+26710342453173446398987920*a(n-37)-56091719151664237437874632*a(n-38)+42973718542999741813111920*a(n-39)-429737185429997418131119200*a(n-40)+902448089402994578075350320*a(n-41)-524945753995638939106975200*a(n-42)+5249457539956389391069752000*a(n-43)-11023860833908417721246479200*a(n-44)+4808879538561612672778008000*a(n-45)-48088795385616126727780080000*a(n-46)+100986470309793866128338168000*a(n-47)-32452815343848522029571600000*a(n-48)+324528153438485220295716000000*a(n-49)-681509122220818962621003600000*a(n-50)+157206092834527473963441600000*a(n-51)-1572060928345274739634416000000*a(n-52)+3301327949525076953232273600000*a(n-53)-525563702247928386006720000000*a(n-54)+5255637022479283860067200000000*a(n-55)-11036837747206496106141120000000*a(n-56)+1137501980268153329088000000000*a(n-57)-11375019802681533290880000000000*a(n-58)+23887541585631219910848000000000*a(n-59)-1416061344057218107200000000000*a(n-60)+14160613440572181072000000000000*a(n-61)-29737288225201580251200000000000*a(n-62)+759486915141786720000000000000*a(n-63)-7594869151417867200000000000000*a(n-64)+15949225217977521120000000000000*a(n-65)

Example

Some solutions for 6X4
..0..0..2..0....0..0..2..0....0..0..2..1....0..0..1..0....0..0..0..0
..1..2..0..1....1..0..2..1....1..1..0..2....1..1..2..2....2..2..2..1
..1..2..1..1....2..2..0..2....2..2..1..0....2..1..1..1....1..2..0..2
..2..0..0..2....0..0..2..0....1..0..1..2....1..0..0..1....0..0..0..0
..0..2..1..0....2..0..1..2....1..1..0..2....1..1..2..2....2..2..2..1
..1..1..2..1....0..2..2..0....2..2..1..0....1..1..2..0....1..0..2..2

Crossrefs

Sequence in context: A035923 A137878 A165598 * A252624 A252513 A328868

Adjacent sequences: A187638 A187639 A187640 * A187642 A187643 A187644

Keyword

nonn

Author

R. H. Hardin Mar 12 2011

Status

approved