A254915 - OEIS

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A254915

Number of (n+2)X(1+2) 0..1 arrays with every 3X3 subblock sum of the two maximums of the central row and central column plus the two minimums of the diagonal and antidiagonal nondecreasing horizontally and vertically

512, 2812, 14184, 65548, 294960, 1302500, 5646340, 24197932, 102910460, 435448220, 1835734148, 7717606664, 32383016692, 135697390944, 568079847724, 2376537629288, 9937162336296, 41536068400632, 173571311968704

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

OFFSET

1,1

COMMENTS

Column 1 of A254922

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) -13*a(n-2) +11*a(n-3) -13*a(n-4) -60*a(n-5) -32*a(n-6) +210*a(n-7) +501*a(n-8) -221*a(n-9) +109*a(n-10) -981*a(n-11) -1875*a(n-12) +1430*a(n-13) +856*a(n-14) -180*a(n-15) +468*a(n-16) -216*a(n-17)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A258530 A254922 A254253 * A257154 A254743 A254736

Adjacent sequences: A254912 A254913 A254914 * A254916 A254917 A254918

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 10 2015

STATUS

approved