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A316879
Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 4, 5, 6 or 7 king-move adjacent elements, with upper left element zero.
1
8, 28, 105, 452, 2401, 11532, 54613, 268142, 1322178, 6448163, 31571732, 155259809, 761566882, 3736254465, 18352493470, 90106217668, 442390202621, 2172549312060, 10668437072408, 52387940298962, 257266803546723, 1263369837323884
OFFSET
1,1
COMMENTS
Column 4 of A316883.
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) +45*a(n-3) -421*a(n-4) -18*a(n-5) -269*a(n-6) +11948*a(n-7) +1592*a(n-8) -18934*a(n-9) -181677*a(n-10) -25135*a(n-11) +457553*a(n-12) +1582248*a(n-13) +282*a(n-14) -4433748*a(n-15) -7474093*a(n-16) +2884171*a(n-17) +19900509*a(n-18) +13435654*a(n-19) -23152625*a(n-20) -34719968*a(n-21) +33376426*a(n-22) +79688089*a(n-23) -28668829*a(n-24) -211039334*a(n-25) -140926502*a(n-26) +183777784*a(n-27) +370867409*a(n-28) +176078945*a(n-29) -117563377*a(n-30) -216310254*a(n-31) -317412851*a(n-32) -321631411*a(n-33) +34862894*a(n-34) +556462778*a(n-35) +443433945*a(n-36) -138088515*a(n-37) -508849584*a(n-38) -95440694*a(n-39) +107798891*a(n-40) +90300396*a(n-41) +6982647*a(n-42) +74492926*a(n-43) +52423902*a(n-44) +19167376*a(n-45) -11313142*a(n-46) -34673630*a(n-47) -27895543*a(n-48) -12664616*a(n-49) -7478433*a(n-50) +6268620*a(n-51) +1259757*a(n-52) +4464150*a(n-53) -253929*a(n-54) +351186*a(n-55) -23730*a(n-56) -22998*a(n-57) +50238*a(n-58) -4510*a(n-59) +1776*a(n-60) -256*a(n-61) for n>63
EXAMPLE
Some solutions for n=5
..0..1..0..0. .0..1..1..1. .0..0..0..0. .0..0..1..0. .0..0..0..0
..0..1..0..0. .1..0..1..1. .0..0..0..0. .1..0..0..0. .0..0..0..0
..1..1..1..0. .1..1..1..1. .0..0..0..1. .0..0..0..0. .1..0..0..0
..1..0..0..0. .1..0..1..1. .1..0..0..0. .0..0..0..0. .0..0..0..1
..1..0..0..0. .0..1..1..1. .0..0..1..0. .1..1..0..0. .0..0..1..0
CROSSREFS
Cf. A316883.
Sequence in context: A110687 A153365 A317149 * A220710 A260935 A289608
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 15 2018
STATUS
approved