A238249 Number of (n+1)X(2+1) 0..1 arrays with 2X2 subblock sums lexicographically nondecreasing columnwise and rowwise.

44, 180, 804, 2818, 9991, 29995, 90225, 241945, 649320, 1605951, 3974215, 9269399, 21628177, 48322967, 107991481, 233776405, 506133563, 1070574873, 2264593031, 4710021487, 9796211590, 20129009598, 41359935334, 84255978136, 171637137305

Offset: 1

Author

R. H. Hardin, Feb 21 2014

Keywords

• nonn

Comments

Column 2 of A238255

Examples

			Some solutions for n=5
..0..1..0....0..1..0....0..0..0....0..0..0....0..0..1....0..0..1....0..0..0
..1..0..1....0..0..0....1..1..1....0..0..0....0..0..1....0..0..1....0..0..0
..1..0..1....1..0..1....0..1..0....0..0..1....0..0..1....1..0..0....0..0..1
..1..1..1....0..0..1....1..1..1....1..0..0....1..1..0....1..1..1....1..1..0
..0..1..1....1..1..0....0..1..1....0..1..1....0..1..1....1..1..0....1..1..1
..1..1..1....0..1..1....1..1..1....0..1..1....1..1..0....1..1..1....1..1..1
		

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +16*a(n-2) -82*a(n-3) -99*a(n-4) +774*a(n-5) +196*a(n-6) -4456*a(n-7) +1106*a(n-8) +17464*a(n-9) -10080*a(n-10) -49212*a(n-11) +40922*a(n-12) +102532*a(n-13) -108728*a(n-14) -159592*a(n-15) +207747*a(n-16) +184428*a(n-17) -296048*a(n-18) -153442*a(n-19) +318857*a(n-20) +83878*a(n-21) -259308*a(n-22) -19872*a(n-23) +157052*a(n-24) -10232*a(n-25) -68768*a(n-26) +12128*a(n-27) +20592*a(n-28) -5472*a(n-29) -3776*a(n-30) +1280*a(n-31) +320*a(n-32) -128*a(n-33)