A254505 Number of (n+2)X(1+2) 0..1 arrays with every 3X3 subblock sum of four medians of central row, central column, diagonal and antidiagonal nondecreasing horizontally, vertically and ne-to-sw antidiagonally

512, 2703, 12730, 55904, 221858, 833037, 2977462, 10225464, 34028886, 110280168, 349551666, 1087417895, 3328908758, 10051170955, 29985882752, 88525404974, 258951023734, 751340000125, 2164314393804, 6194580296317, 17628054712962

Offset

1,1

Comments

Column 1 of A254512

Links

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

Formula

Empirical: a(n) = 8*a(n-1) -18*a(n-2) -4*a(n-3) +55*a(n-4) -110*a(n-5) +286*a(n-6) -186*a(n-7) -316*a(n-8) -32*a(n-9) -1169*a(n-10) +2232*a(n-11) +905*a(n-12) +5582*a(n-13) -1562*a(n-14) -6548*a(n-15) -17521*a(n-16) -24654*a(n-17) +2932*a(n-18) +29434*a(n-19) +104091*a(n-20) +96978*a(n-21) +69129*a(n-22) -165746*a(n-23) -281974*a(n-24) -513710*a(n-25) -188993*a(n-26) +76236*a(n-27) +936218*a(n-28) +1171854*a(n-29) +1168944*a(n-30) +51308*a(n-31) -1272784*a(n-32) -2365146*a(n-33) -2546636*a(n-34) -1128010*a(n-35) +745904*a(n-36) +3210700*a(n-37) +3372763*a(n-38) +2747224*a(n-39) -268876*a(n-40) -1446746*a(n-41) -3560560*a(n-42) -2210528*a(n-43) -1562533*a(n-44) +880788*a(n-45) +1561288*a(n-46) +977980*a(n-47) +1343536*a(n-48) -161752*a(n-49) +442908*a(n-50) -967760*a(n-51) -131440*a(n-52) -321792*a(n-53) +43952*a(n-54) -13632*a(n-55) +20736*a(n-56) +76032*a(n-57) +20736*a(n-58) for n>59

Example

Some solutions for n=4
..1..0..1....0..1..1....1..1..1....1..1..1....0..0..0....1..1..0....1..1..0
..0..1..0....0..0..1....1..0..0....0..0..1....0..0..1....0..0..0....0..0..1
..1..1..1....1..0..1....1..1..1....0..0..0....0..0..1....1..0..1....0..1..0
..1..1..0....0..1..1....1..1..0....0..0..0....0..1..0....1..0..0....0..1..1
..1..1..0....0..1..1....1..1..0....1..0..1....0..1..1....0..1..1....1..1..0
..1..1..1....0..0..1....1..0..1....1..0..0....0..1..1....0..0..1....1..0..1

Crossrefs

Sequence in context: A253813 A254512 A254819 * A253993 A258910 A253986

Adjacent sequences: A254502 A254503 A254504 * A254506 A254507 A254508

Keyword

nonn

Author

R. H. Hardin, Jan 31 2015

Status

approved