A235976 Number of (n+1)X(3+1) 0..2 arrays with the upper median equal to the lower median in every 2X2 subblock

815, 11239, 143183, 1947197, 26090277, 354374671, 4798700327, 65170792525, 884485021717, 12011793919475, 163101327680283, 2214982423225533, 30079237388747229, 408486630209059715, 5547341478977062431

Offset

1,1

Comments

Column 3 of A235981

Links

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

Formula

Empirical: a(n) = 16*a(n-1) +65*a(n-2) -1595*a(n-3) +223*a(n-4) +56171*a(n-5) -84933*a(n-6) -888167*a(n-7) +1946673*a(n-8) +6753582*a(n-9) -18488606*a(n-10) -22612278*a(n-11) +83476711*a(n-12) +13913001*a(n-13) -169841884*a(n-14) +68228390*a(n-15) +120510376*a(n-16) -85856240*a(n-17) -18639208*a(n-18) +25880752*a(n-19) -3208928*a(n-20) -1414464*a(n-21) +280064*a(n-22)

Example

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

Crossrefs

Sequence in context: A099116 A183820 A272606 * A015159 A250803 A251205

Adjacent sequences: A235973 A235974 A235975 * A235977 A235978 A235979

Keyword

nonn

Author

R. H. Hardin, Jan 17 2014

Status

approved