A235976 - OEIS

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

(list; graph; refs; listen; history; text; internal format)

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