A252059 Number of (n+2)X(2+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 1 2 or 4

200, 346, 817, 2081, 5610, 15593, 43618, 122839, 347075, 981466, 2777062, 7859985, 22247952, 62976844, 178273840, 504659106, 1428597686, 4044117989, 11448226797, 32408025216, 91741786804, 259705969673, 735184974976, 2081188160674

Offset

1,1

Comments

Column 2 of A252065

Links

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

Formula

Empirical: a(n) = 3*a(n-1) -a(n-2) +10*a(n-3) -24*a(n-4) +a(n-5) -27*a(n-6) +62*a(n-7) +7*a(n-8) +27*a(n-9) -51*a(n-10) -2*a(n-11) -9*a(n-12) -37*a(n-13) -48*a(n-14) -a(n-15) +95*a(n-16) +85*a(n-17) +9*a(n-18) -55*a(n-19) -46*a(n-20) -16*a(n-21) -7*a(n-23) +6*a(n-24) +13*a(n-25) +13*a(n-26) +4*a(n-27) -5*a(n-28) -3*a(n-29) -2*a(n-30) for n>32

Example

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

Crossrefs

Sequence in context: A247399 A078492 A166256 * A004966 A117412 A109632

Adjacent sequences: A252056 A252057 A252058 * A252060 A252061 A252062

Keyword

nonn

Author

R. H. Hardin, Dec 13 2014

Status

approved