A235957 - OEIS

A235957

Number of (n+1)X(3+1) 0..1 arrays with the difference of the upper and lower median value of each 2X2 subblock in lexicographically nondecreasing order columnwise and nonincreasing rowwise

144, 928, 5196, 27296, 137988, 681546, 3311312, 15908352, 75789960, 358924192, 1692140136, 7951451162, 37271897084, 174391909248, 814845026092, 3803491428248, 17740156559908, 82696152825954, 385325015689600

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OFFSET

1,1

COMMENTS

Column 3 of A235962

LINKS

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

FORMULA

Empirical: a(n) = 9*a(n-1) -a(n-2) -189*a(n-3) +346*a(n-4) +1436*a(n-5) -4035*a(n-6) -4541*a(n-7) +20333*a(n-8) +2377*a(n-9) -52394*a(n-10) +19916*a(n-11) +68520*a(n-12) -46336*a(n-13) -39744*a(n-14) +35328*a(n-15) +7168*a(n-16) -8192*a(n-17)

EXAMPLE

Some solutions for n=4

..1..0..1..0....0..1..1..1....0..0..1..1....1..0..1..0....0..0..0..1

..0..0..0..1....1..1..0..0....0..0..0..0....1..1..0..1....0..0..0..1

..0..0..0..1....1..1..1..1....0..0..0..1....1..1..1..0....1..0..1..0

..0..0..0..0....0..1..0..1....1..0..0..0....0..1..0..0....1..1..1..0

..1..0..1..0....0..0..0..0....0..0..1..0....1..1..1..0....1..1..1..0

CROSSREFS

Sequence in context: A187301 A120089 A159748 * A162669 A230796 A230789

Adjacent sequences: A235954 A235955 A235956 * A235958 A235959 A235960

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 17 2014

STATUS

approved