A252212 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 5 6 or 7

874, 1212, 1843, 3147, 5011, 8178, 14627, 26610, 50441, 99604, 200704, 417343, 882057, 1884329, 4067714, 8836577, 19282718, 42207024, 92542991, 203209693, 446662969, 982320854, 2161276673, 4756530458, 10470069046, 23049757003

Offset

1,1

Comments

Column 1 of A252219

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 2*a(n-1) -a(n-2) +14*a(n-3) -14*a(n-4) +9*a(n-5) -90*a(n-6) +14*a(n-7) -80*a(n-8) +274*a(n-9) +109*a(n-10) +389*a(n-11) -303*a(n-12) -261*a(n-13) -785*a(n-14) -134*a(n-15) +86*a(n-16) +331*a(n-17) +164*a(n-18) -349*a(n-19) +742*a(n-20) +953*a(n-21) +2003*a(n-22) -408*a(n-23) -1522*a(n-24) -2586*a(n-25) -75*a(n-26) +1557*a(n-27) +16*a(n-28) -3412*a(n-29) -5380*a(n-30) +872*a(n-31) +8659*a(n-32) +13315*a(n-33) +5226*a(n-34) -7618*a(n-35) -16921*a(n-36) -13179*a(n-37) -564*a(n-38) +10240*a(n-39) +13048*a(n-40) +6865*a(n-41) +383*a(n-42) -4898*a(n-43) -5836*a(n-44) -5619*a(n-45) -2530*a(n-46) +1372*a(n-47) +4502*a(n-48) +4329*a(n-49) +1340*a(n-50) -1580*a(n-51) -2514*a(n-52) -1372*a(n-53) +28*a(n-54) +682*a(n-55) +516*a(n-56) +152*a(n-57) -48*a(n-58) -72*a(n-59) -32*a(n-60) -8*a(n-61) for n>69

Example

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

Crossrefs

Sequence in context: A252211 A045258 A252219 * A376749 A038658 A065700

Adjacent sequences: A252209 A252210 A252211 * A252213 A252214 A252215

Keyword

nonn

Author

R. H. Hardin, Dec 15 2014

Status

approved