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A278276
Number of nX4 0..1 arrays with every element both equal and not equal to some elements at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero.
1
0, 13, 122, 1461, 16842, 196726, 2293193, 26748095, 311952675, 3638315600, 42433460041, 494899976008, 5771998528706, 67318594537535, 785134131756525, 9156988685842075, 106797600929943552, 1245576243371149125
OFFSET
1,2
COMMENTS
Column 4 of A278280.
LINKS
FORMULA
Empirical: a(n) = 10*a(n-1) +30*a(n-2) -106*a(n-3) -241*a(n-4) +350*a(n-5) +671*a(n-6) -325*a(n-7) +128*a(n-8) -1128*a(n-9) -1075*a(n-10) +524*a(n-11) -119*a(n-12) +331*a(n-13) +274*a(n-14) -179*a(n-15) +42*a(n-16) -6*a(n-17) for n>19
EXAMPLE
Some solutions for n=4
..0..0..1..1. .0..0..1..1. .0..1..1..1. .0..1..1..0. .0..0..0..1
..1..1..0..0. .1..1..0..0. .0..1..0..0. .0..1..0..0. .1..1..0..1
..1..0..1..0. .1..1..0..1. .1..0..1..0. .0..1..1..0. .1..0..0..0
..0..1..0..1. .0..0..0..1. .1..1..0..1. .0..1..0..1. .0..1..1..0
CROSSREFS
Cf. A278280.
Sequence in context: A339057 A016230 A327961 * A201382 A101186 A295778
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 16 2016
STATUS
approved