A240003 Number of 4Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest, modulo 4.
28, 256, 1372, 6527, 27415, 104291, 363859, 1173141, 3539402, 10055917, 27072084, 69433880, 170442542, 402042194, 914489241, 2012051851, 4293710454, 8908363984, 18007433696, 35530979384, 68546844725, 129490989279, 239852605993
Offset: 1
Keywords
Examples
Some solutions for n=5 ..0..0..0..3..3....0..3..3..0..0....0..0..0..0..0....0..0..0..0..3 ..0..0..3..3..2....0..0..3..1..0....0..0..0..3..3....3..3..0..0..0 ..3..3..0..2..2....0..3..3..1..3....3..3..0..2..2....2..2..3..3..0 ..0..2..2..0..3....0..2..1..2..3....3..2..1..2..2....2..1..3..2..2
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = (1/30411275102208000)*n^19 + (1/914624815104000)*n^18 + (397/2134124568576000)*n^17 + (37/62768369664000)*n^16 + (2567/6276836966400)*n^15 - (77899/8966909952000)*n^14 + (121042813/188305108992000)*n^13 - (5389171/258660864000)*n^12 + (469998043/603542016000)*n^11 - (20022197893/877879296000)*n^10 + (5869313250161/9656672256000)*n^9 - (9505177279259/689762304000)*n^8 + (12579369755410273/47076277248000)*n^7 - (3647143231803217/840647808000)*n^6 + (50430900400493621/871782912000)*n^5 - (804068701944948239/1307674368000)*n^4 + (64298607619642973/12864852000)*n^3 - (25675604169133123/882161280)*n^2 + (25119199779142691/232792560)*n - 191027452 for n>20
Comments