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A235760 Number of (n+1)X(3+1) 0..1 arrays with the sum of each 2X2 subblock two median terms lexicographically nondecreasing columnwise and nonincreasing rowwise 1
141, 977, 6882, 41446, 242684, 1310058, 6840001, 34087789, 165068548, 775598494, 3562426975, 16017777604, 70763909432, 307697458346, 1319740103323, 5591683329070, 23438083323919, 97303006036084, 400509298117315 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 3 of A235765
LINKS
FORMULA
Empirical: a(n) = 21*a(n-1) -154*a(n-2) +216*a(n-3) +3102*a(n-4) -15362*a(n-5) -8010*a(n-6) +227638*a(n-7) -346453*a(n-8) -1667959*a(n-9) +5293502*a(n-10) +5913596*a(n-11) -40977903*a(n-12) +4490375*a(n-13) +207977376*a(n-14) -176830602*a(n-15) -745036126*a(n-16) +1113969734*a(n-17) +1909476924*a(n-18) -4364931308*a(n-19) -3327846891*a(n-20) +12414234111*a(n-21) +2926950230*a(n-22) -27049487256*a(n-23) +3161362257*a(n-24) +46248491955*a(n-25) -17923984610*a(n-26) -62647257108*a(n-27) +39042123170*a(n-28) +67187956474*a(n-29) -57699545498*a(n-30) -56372293146*a(n-31) +64098745925*a(n-32) +35855979111*a(n-33) -55387030614*a(n-34) -15906775348*a(n-35) +37647675071*a(n-36) +3461774001*a(n-37) -20115999844*a(n-38) +1185897478*a(n-39) +8365429502*a(n-40) -1543037022*a(n-41) -2652640376*a(n-42) +792816240*a(n-43) +618128251*a(n-44) -258968623*a(n-45) -98545950*a(n-46) +57118960*a(n-47) +8963328*a(n-48) -8298400*a(n-49) -107584*a(n-50) +720640*a(n-51) -63232*a(n-52) -28416*a(n-53) +4608*a(n-54)
EXAMPLE
Some solutions for n=4
..0..1..1..1....0..1..1..1....1..1..1..1....0..1..1..1....1..0..1..1
..0..1..1..1....0..1..1..1....0..1..0..1....1..1..1..1....1..1..1..1
..0..0..0..1....0..0..1..1....1..0..1..0....1..0..1..0....0..1..1..0
..0..0..0..0....1..0..0..1....1..0..1..0....0..0..1..0....0..0..0..1
..1..0..0..0....0..0..0..0....0..0..0..1....0..0..1..0....0..0..1..1
CROSSREFS
Sequence in context: A255154 A068046 A186954 * A201814 A235543 A204469
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 15 2014
STATUS
approved

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Last modified March 2 21:08 EST 2024. Contains 370498 sequences. (Running on oeis4.)