A252559 Number of (1+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 1 2 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 1 2 4 6 or 7

771, 1107, 1510, 2443, 4284, 7755, 13917, 27182, 51187, 94813, 189576, 362736, 678322, 1360865, 2614578, 4907897, 9838034, 18931643, 35616087, 71259620, 137248851, 258672971, 516507423, 995487746, 1879267853, 3745133076

Offset

1,1

Comments

Row 1 of A252558

Links

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

Formula

Empirical: a(n) = 25*a(n-3) +2*a(n-4) -239*a(n-6) -43*a(n-7) -a(n-8) +1103*a(n-9) +334*a(n-10) +17*a(n-11) -2670*a(n-12) -1108*a(n-13) -84*a(n-14) +3919*a(n-15) +1405*a(n-16) +17*a(n-17) -4053*a(n-18) -354*a(n-19) +805*a(n-20) +3346*a(n-21) -1100*a(n-22) -1994*a(n-23) -2345*a(n-24) +2032*a(n-25) +2624*a(n-26) +1431*a(n-27) -2128*a(n-28) -2602*a(n-29) -817*a(n-30) +1501*a(n-31) +1921*a(n-32) +463*a(n-33) -754*a(n-34) -1063*a(n-35) -216*a(n-36) +276*a(n-37) +468*a(n-38) +81*a(n-39) -63*a(n-40) -135*a(n-41) -27*a(n-42) +27*a(n-44) for n>60

Example

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

Crossrefs

Sequence in context: A045078 A252550 A252558 * A259696 A114543 A233647

Adjacent sequences: A252556 A252557 A252558 * A252560 A252561 A252562

Keyword

nonn

Author

R. H. Hardin, Dec 18 2014

Status

approved