A252210 T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 1 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 1 3 4 6 or 7

2680, 4743, 4743, 9312, 5178, 9312, 19794, 17276, 17276, 19794, 51024, 44322, 110128, 44322, 51024, 125554, 215814, 332462, 332462, 215814, 125554, 278710, 932474, 2908856, 1180226, 2908856, 932474, 278710, 763726, 2568954, 22430534

Offset

1,1

Comments

Table starts

....2680......4743........9312.......19794..........51024..........125554

....4743......5178.......17276.......44322.........215814..........932474

....9312.....17276......110128......332462........2908856........22430534

...19794.....44322......332462.....1180226.......11207238........84935426

...51024....215814.....2908856....11207238......193004794......2778728210

..125554....932474....22430534....84935426.....2778728210.....78534150994

..278710...2568954....65275092...301990806....10519316686....267361717782

..763726..12883538...634915114..2868905558...185237248134...9906342079298

.1944090..56985498..5227154036.21743274306..2757905885304.303070072293522

.4393122.157484310.14646511730.77309414066.10320806426406.959873651074130

Links

R. H. Hardin, Table of n, a(n) for n = 1..480

Formula

Empirical for column k:

k=1: [linear recurrence of order 21] for n>26

k=2: [order 21] for n>25

k=3: [order 21] for n>24

k=4: a(n) = 260*a(n-3) -1023*a(n-6) -260*a(n-9) +1024*a(n-12) for n>15

k=5: [order 21] for n>24

k=6: [order 21] for n>24

k=7: a(n) = 4104*a(n-3) -32767*a(n-6) -4104*a(n-9) +32768*a(n-12) for n>15

Example

Some solutions for n=3 k=4
..0..1..3..0..1..3....1..0..3..1..3..0....2..1..1..2..1..1....0..1..3..3..1..0
..3..1..0..3..1..3....3..2..2..3..2..2....1..3..0..1..0..0....0..1..0..3..1..0
..1..2..1..1..2..1....0..2..2..3..2..2....1..0..0..1..0..0....1..2..1..1..2..1
..0..1..3..0..1..0....1..0..3..1..3..3....2..1..1..2..1..1....0..1..0..3..1..0
..0..1..0..0..1..3....3..2..2..0..2..2....1..3..3..1..3..0....3..1..3..3..1..3

Crossrefs

Sequence in context: A258505 A258512 A254992 * A252203 A252202 A236594

Adjacent sequences: A252207 A252208 A252209 * A252211 A252212 A252213

Keyword

nonn,tabl

Author

R. H. Hardin, Dec 15 2014

Status

approved