A252027 Number of (n+2) X (3+2) 0..2 arrays with every 3 X 3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 or 4.

357, 781, 2206, 7182, 24664, 85199, 295050, 1022761, 3550805, 12331430, 42824128, 148745714, 516732733, 1795122228, 6236192559, 21664447059, 75262834840, 261466468666, 908345208354, 3155624010041, 10962763943176, 38085122179431

Offset

1,1

Comments

Column 3 of A252032.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -5*a(n-2) +18*a(n-3) -17*a(n-4) -5*a(n-5) -65*a(n-6) -76*a(n-7) +133*a(n-8) +215*a(n-9) +211*a(n-10) -318*a(n-11) -191*a(n-12) -34*a(n-13) +174*a(n-14) +288*a(n-15) -356*a(n-16) -568*a(n-17) -431*a(n-18) +165*a(n-19) +589*a(n-20) +542*a(n-21) +244*a(n-22) +7*a(n-23) -137*a(n-24) -138*a(n-25) -140*a(n-26) -72*a(n-27) -32*a(n-28) -4*a(n-29) for n > 33.

Example

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

Crossrefs

Cf. A252032.

Sequence in context: A357775 A052479 A252806 * A241931 A166916 A166913

Adjacent sequences: A252024 A252025 A252026 * A252028 A252029 A252030

Keyword

nonn

Author

R. H. Hardin, Dec 12 2014

Status

approved