A236980 Number of (n+1)X(1+1) 0..3 arrays with the maximum plus the upper median plus the lower median of every 2X2 subblock equal

256, 888, 3000, 11388, 43096, 171036, 680872, 2770540, 11314280, 46745212, 193702392, 808182812, 3379755176, 14195483212, 59730878232, 252065800108, 1065257795496, 4511108677852, 19125825557240, 81209035684796

Offset

1,1

Comments

Column 1 of A236987

Links

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

Formula

Empirical: a(n) = 18*a(n-1) -49*a(n-2) -974*a(n-3) +6544*a(n-4) +15552*a(n-5) -239242*a(n-6) +153500*a(n-7) +4593459*a(n-8) -10260182*a(n-9) -52330353*a(n-10) +196342530*a(n-11) +342078502*a(n-12) -2201198668*a(n-13) -754500084*a(n-14) +16383893648*a(n-15) -7843044456*a(n-16) -84185730992*a(n-17) +91336550688*a(n-18) +299169566880*a(n-19) -494453981312*a(n-20) -710291341312*a(n-21) +1690514443008*a(n-22) +1001466854912*a(n-23) -3875588317184*a(n-24) -416161998848*a(n-25) +5974812073984*a(n-26) -1228457795584*a(n-27) -6020740644864*a(n-28) +2548308574208*a(n-29) +3735935254528*a(n-30) -2188695306240*a(n-31) -1288941600768*a(n-32) +933983944704*a(n-33) +210685132800*a(n-34) -187026112512*a(n-35) -11324620800*a(n-36) +13589544960*a(n-37)

Example

Some solutions for n=5
..2..0....3..1....1..2....1..2....2..1....0..2....1..3....1..3....1..2....2..0
..0..3....2..1....2..2....0..2....2..2....2..2....3..1....2..3....1..3....2..1
..0..2....1..3....2..1....3..0....0..2....2..0....2..2....0..3....0..2....1..2
..3..0....1..2....0..3....2..0....1..3....2..2....2..3....3..2....3..1....2..1
..1..1....0..3....3..0....1..2....2..1....1..2....2..2....2..3....2..1....1..2
..1..3....1..2....3..0....2..1....3..1....3..0....0..3....3..2....3..1....0..2

Crossrefs

Sequence in context: A258733 A209381 A236987 * A224975 A237090 A224968

Adjacent sequences: A236977 A236978 A236979 * A236981 A236982 A236983

Keyword

nonn

Author

R. H. Hardin, Feb 02 2014

Status

approved