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A302873
Number of nX4 0..1 arrays with every element equal to 0, 1, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1
5, 21, 35, 95, 285, 858, 2938, 11126, 44216, 186565, 819633, 3681703, 16781413, 77160382, 356502109, 1651886591, 7666887125, 35617442101, 165553926866, 769750431744, 3579614404889, 16648148072359, 77431993155630
OFFSET
1,1
COMMENTS
Column 4 of A302877.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -a(n-2) +9*a(n-3) -38*a(n-4) -64*a(n-5) -94*a(n-6) -28*a(n-7) +298*a(n-8) +645*a(n-9) +892*a(n-10) +2073*a(n-11) +2812*a(n-12) +1062*a(n-13) -6119*a(n-14) -14380*a(n-15) -15795*a(n-16) -13646*a(n-17) -10955*a(n-18) -6874*a(n-19) +13030*a(n-20) +34925*a(n-21) +45526*a(n-22) +34585*a(n-23) +42419*a(n-24) +53978*a(n-25) +38220*a(n-26) -24564*a(n-27) -75371*a(n-28) -85828*a(n-29) -61780*a(n-30) -29630*a(n-31) -7671*a(n-32) +10349*a(n-33) +15109*a(n-34) +19873*a(n-35) +15144*a(n-36) +11837*a(n-37) +4645*a(n-38) +3040*a(n-39) +2158*a(n-40) +65*a(n-41) -120*a(n-42) -1013*a(n-43) +241*a(n-44) -225*a(n-45) +495*a(n-46) +126*a(n-47) +306*a(n-48) +42*a(n-49) +54*a(n-50) +8*a(n-51) -34*a(n-52) -6*a(n-53) -18*a(n-54) -2*a(n-55) -2*a(n-56) for n>59
EXAMPLE
Some solutions for n=5
..0..1..0..0. .0..0..1..0. .0..1..0..1. .0..0..0..1. .0..1..0..1
..0..1..1..1. .1..1..1..0. .0..1..0..1. .0..1..1..1. .0..1..0..1
..0..1..0..1. .1..0..1..0. .0..1..1..0. .0..1..0..1. .0..1..0..1
..0..1..0..1. .1..0..1..0. .1..0..1..0. .0..1..0..1. .0..1..1..1
..0..1..1..0. .0..1..1..0. .1..0..1..0. .1..0..0..1. .0..1..0..0
CROSSREFS
Cf. A302877.
Sequence in context: A145026 A039561 A063575 * A170837 A170876 A373193
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 15 2018
STATUS
approved