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A209371
Number of nX5 1..3 arrays with no element with value z exactly a city block distance of z from another element with value z
1
64, 178, 690, 3698, 19434, 99458, 510378, 2622050, 13507474, 69549218, 357584194, 1839211250, 9464568582, 48696339042, 250509806670, 1288779804242, 6630621737430, 34113122683362, 175501749819570, 902909367872738
OFFSET
1,1
COMMENTS
Column 5 of A209374
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +35*a(n-3) +85*a(n-4) +99*a(n-5) +163*a(n-6) +149*a(n-7) +573*a(n-8) -641*a(n-9) -3453*a(n-10) +1807*a(n-11) +10816*a(n-12) +2900*a(n-13) -7862*a(n-14) -5427*a(n-15) +2707*a(n-16) +6158*a(n-17) +6821*a(n-18) +3904*a(n-19) +6005*a(n-20) -777*a(n-21) -2314*a(n-22) -3245*a(n-23) -2119*a(n-24) -163*a(n-25) -1022*a(n-26) +136*a(n-27) -431*a(n-28) -46*a(n-29) -91*a(n-30) +33*a(n-31) -14*a(n-32) +9*a(n-33) -2*a(n-35) +a(n-36) for n>38
EXAMPLE
Some solutions for n=5
..3..1..2..1..3....3..1..3..2..2....1..3..2..2..1....3..2..3..1..2
..1..3..2..3..1....2..2..1..3..1....2..1..3..1..3....1..3..1..3..1
..3..1..3..1..3....3..1..3..1..3....1..3..1..3..1....2..1..3..1..3
..1..2..1..3..2....1..3..1..3..1....3..2..3..1..2....1..3..1..3..1
..3..2..3..1..2....2..1..3..1..3....1..3..1..3..1....3..1..2..1..3
CROSSREFS
Sequence in context: A209379 A203448 A078093 * A317763 A318342 A318074
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 07 2012
STATUS
approved