login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A276303
Number of 6Xn 0..2 arrays with no element equal to any value at offset (-2,-1) (-1,1) or (0,-1) and new values introduced in order 0..2.
1
122, 250, 3437, 34865, 442001, 4988145, 59728757, 693817033, 8184858377, 95798120125, 1125757112093, 13202147428061, 154987529747569, 1818521601523949, 21343104642406881, 250459145656655937
OFFSET
1,1
COMMENTS
Row 6 of A276299.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +78*a(n-2) +250*a(n-3) +558*a(n-4) -937*a(n-5) -4256*a(n-6) -7991*a(n-7) -3472*a(n-8) +31381*a(n-9) -11144*a(n-10) +42683*a(n-11) -198936*a(n-12) +231086*a(n-13) -131301*a(n-14) +70502*a(n-15) -27827*a(n-16) +159651*a(n-17) -217780*a(n-18) +120250*a(n-19) -55920*a(n-20) -17125*a(n-21) +26805*a(n-22) -25487*a(n-23) +30226*a(n-24) -15183*a(n-25) +5503*a(n-26) -1930*a(n-27) +371*a(n-28) -65*a(n-29) +8*a(n-30) for n>32
EXAMPLE
Some solutions for n=4
..0..1..2..0. .0..1..0..2. .0..1..2..1. .0..1..2..1. .0..1..0..1
..2..1..2..0. .0..2..0..1. .0..1..2..1. .0..1..0..1. .2..1..0..1
..2..1..2..1. .1..2..0..1. .2..1..0..1. .0..1..2..1. .2..1..0..1
..0..1..0..1. .0..2..0..1. .0..1..0..1. .2..1..2..1. .0..1..0..2
..0..1..0..1. .1..2..0..2. .0..1..0..1. .2..1..2..0. .0..1..0..1
..0..1..2..1. .0..1..0..1. .0..2..0..2. .2..0..2..1. .2..1..0..1
CROSSREFS
Cf. A276299.
Sequence in context: A158131 A004925 A369598 * A224598 A070955 A195856
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 28 2016
STATUS
approved