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A253700 Number of (3+1)X(n+1) 0..1 arrays with every 2X2 subblock ne-sw antidiagonal difference unequal to its neighbors horizontally and nw+se diagonal sum unequal to its neighbors vertically 1
104, 146, 234, 356, 618, 968, 1608, 2558, 4278, 6854, 11266, 18192, 29910, 48348, 79116, 128376, 209934, 340652, 556268, 904160, 1475412, 2398716, 3911988, 6364810, 10375264, 16884488, 27516618, 44793406, 72982490, 118821772 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 3 of A253698

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-2) +2*a(n-4) +2*a(n-5) -3*a(n-6) +a(n-7) -a(n-8) -6*a(n-9) +2*a(n-10) -2*a(n-12) -3*a(n-13) +a(n-14) +6*a(n-15) +a(n-16) +a(n-17) -a(n-18) -a(n-19) for n>21

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A274357 A052476 A297912 * A260922 A054903 A074228

Adjacent sequences:  A253697 A253698 A253699 * A253701 A253702 A253703

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 09 2015

STATUS

approved

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Last modified March 8 08:16 EST 2021. Contains 341942 sequences. (Running on oeis4.)