A253401 Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock diagonal maximum plus antidiagonal minimum unequal to its neighbors horizontally, vertically and ne+sw antidiagonally

480, 2192, 8168, 37828, 158472, 638602, 2763096, 11635116, 48192624, 204426054, 860035398, 3595579764, 15165108854, 63753731972, 267437028486, 1125578669222, 4730926644910, 19870579277538, 83560330431412, 351201530231424

Offset

1,1

Comments

Column 2 of A253407

Links

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

Formula

Empirical: a(n) = 4*a(n-2) +72*a(n-3) +68*a(n-4) -8*a(n-5) -1662*a(n-6) -2882*a(n-7) -4020*a(n-8) +14034*a(n-9) +38816*a(n-10) +48860*a(n-11) -39397*a(n-12) -354278*a(n-13) -270037*a(n-14) -181370*a(n-15) +2083774*a(n-16) +1464856*a(n-17) +1775183*a(n-18) -7002380*a(n-19) -6112592*a(n-20) -1400676*a(n-21) +9099984*a(n-22) +11717488*a(n-23) -16944264*a(n-24) -6072844*a(n-25) -62270180*a(n-26) +93061288*a(n-27) +58377220*a(n-28) -365646896*a(n-29) -152674404*a(n-30) +341462592*a(n-31) +1081243968*a(n-32) +378105536*a(n-33) +55147760*a(n-34) +185007872*a(n-35) +59550720*a(n-36) -4139520*a(n-37) +6423552*a(n-38) +2101248*a(n-39) -331776*a(n-40) for n>42

Example

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

Crossrefs

Sequence in context: A258558 A083728 A199808 * A327944 A357493 A063870

Adjacent sequences: A253398 A253399 A253400 * A253402 A253403 A253404

Keyword

nonn

Author

R. H. Hardin, Dec 31 2014

Status

approved