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A205090 Number of (n+1)X2 0..3 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock equal to the number in all its horizontal and vertical neighbors 1
256, 1328, 8176, 55848, 401164, 2965056, 22161076, 166572246, 1254940334, 9466169218, 71445543963, 539397114979, 4072935596742, 30756750419559, 232268549150385, 1754078998631223, 13246841683912513, 100040954964697326 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A205097

LINKS

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

FORMULA

Empirical: a(n) = 13*a(n-1) -43*a(n-2) -31*a(n-3) +492*a(n-4) -1254*a(n-5) +378*a(n-6) +4294*a(n-7) -9634*a(n-8) +11950*a(n-9) -9176*a(n-10) -7034*a(n-11) +32979*a(n-12) -48847*a(n-13) +51554*a(n-14) -57136*a(n-15) +75170*a(n-16) -93014*a(n-17) +108855*a(n-18) -135255*a(n-19) +143481*a(n-20) -117173*a(n-21) +86814*a(n-22) -56300*a(n-23) +22871*a(n-24) -3267*a(n-25) -2926*a(n-26) +4318*a(n-27) -3158*a(n-28) +1328*a(n-29) -152*a(n-30) -128*a(n-31) +32*a(n-32) for n>35

EXAMPLE

Some solutions for n=4

..1..3....2..1....1..1....3..1....1..0....1..0....3..3....1..2....0..1....1..0

..0..2....1..3....2..0....1..3....0..3....0..0....2..0....3..2....1..0....3..2

..0..1....2..0....2..1....0..1....0..1....0..0....0..0....0..3....3..2....2..3

..0..1....3..1....2..2....0..1....1..1....0..0....0..0....1..0....1..3....2..3

..0..1....1..2....3..1....1..0....1..3....0..0....0..0....3..3....1..2....3..0

CROSSREFS

Sequence in context: A237398 A237392 A205097 * A231943 A206327 A242257

Adjacent sequences:  A205087 A205088 A205089 * A205091 A205092 A205093

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2012

STATUS

approved

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Last modified January 23 21:55 EST 2021. Contains 340386 sequences. (Running on oeis4.)