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A281397
Number of nX5 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
1
0, 170, 689, 2146, 5892, 13446, 30959, 73600, 169161, 384546, 874926, 1975442, 4434817, 9919920, 22098196, 49065818, 108622142, 239782662, 528047528, 1160306466, 2544313452, 5568815362, 12167899747, 26544765678, 57823995949
OFFSET
1,2
COMMENTS
Column 5 of A281400.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) -a(n-2) +5*a(n-3) -15*a(n-4) -5*a(n-5) -4*a(n-6) +22*a(n-7) +44*a(n-8) -6*a(n-9) -23*a(n-10) -73*a(n-11) -16*a(n-12) +48*a(n-13) +39*a(n-14) +37*a(n-15) -33*a(n-16) -39*a(n-17) +9*a(n-18) +9*a(n-19) for n>30
EXAMPLE
Some solutions for n=4
..0..1..0..0..1. .0..0..1..0..0. .0..0..1..1..0. .0..0..1..1..0
..1..1..0..1..1. .1..0..1..0..1. .1..1..0..0..0. .1..0..1..1..0
..1..0..0..1..0. .1..1..1..0..0. .0..1..0..1..0. .0..0..1..0..1
..0..1..0..1..0. .0..0..0..1..1. .0..1..0..1..0. .0..1..1..0..0
CROSSREFS
Cf. A281400.
Sequence in context: A031704 A173275 A301867 * A206122 A259293 A262426
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 21 2017
STATUS
approved