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A297939
Number of nX4 0..1 arrays with every element equal to 0, 2, 3 or 5 king-move adjacent elements, with upper left element zero.
1
1, 18, 14, 33, 74, 226, 694, 2121, 6517, 20208, 62318, 194028, 605018, 1886146, 5880293, 18345280, 57237337, 178610253, 557469488, 1740070101, 5431575417, 16955289509, 52929706608, 165234844426, 515834559905, 1610365247145
OFFSET
1,2
COMMENTS
Column 4 of A297943.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -4*a(n-2) -6*a(n-3) -2*a(n-5) +7*a(n-6) +25*a(n-7) -138*a(n-8) +337*a(n-9) +138*a(n-10) -395*a(n-11) -142*a(n-12) +42*a(n-13) -615*a(n-14) -908*a(n-15) +868*a(n-16) +508*a(n-17) +1786*a(n-18) -1786*a(n-19) +5578*a(n-20) +2452*a(n-21) -6498*a(n-22) -346*a(n-23) -2236*a(n-24) +3066*a(n-25) -15373*a(n-26) +3849*a(n-27) -5004*a(n-28) +17076*a(n-29) -8273*a(n-30) +1788*a(n-31) +19849*a(n-32) -10967*a(n-33) +16874*a(n-34) -27152*a(n-35) +24985*a(n-36) -38369*a(n-37) +31345*a(n-38) -19376*a(n-39) +16925*a(n-40) -23192*a(n-41) +10806*a(n-42) +640*a(n-43) +6694*a(n-44) -7394*a(n-45) +6017*a(n-46) -4495*a(n-47) -1709*a(n-48) +265*a(n-49) +2439*a(n-50) +286*a(n-51) +259*a(n-52) -471*a(n-53) -101*a(n-54) -8*a(n-55) +68*a(n-56) -16*a(n-57) for n>59
EXAMPLE
Some solutions for n=7
..0..0..0..0. .0..1..0..0. .0..1..0..1. .0..1..0..0. .0..1..0..0
..0..1..1..0. .1..1..1..0. .1..1..1..1. .0..0..0..1. .0..0..0..1
..1..0..0..1. .0..0..0..1. .1..0..1..0. .0..1..1..1. .1..1..0..0
..1..1..1..0. .0..1..1..1. .0..0..0..0. .0..1..0..1. .1..0..1..0
..1..0..1..0. .1..0..0..0. .0..1..0..1. .0..0..0..1. .1..0..1..1
..1..0..0..1. .0..1..1..0. .1..1..0..0. .0..1..1..0. .1..1..0..0
..1..1..1..1. .0..0..1..1. .0..1..0..1. .1..1..0..0. .0..1..1..0
CROSSREFS
Cf. A297943.
Sequence in context: A040308 A077810 A232505 * A298550 A160901 A159502
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 09 2018
STATUS
approved