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A190099 Number of 1:2:sqrt(5) proportioned triangles on an (n+1) X (n+1) grid. 2
0, 16, 64, 176, 384, 744, 1288, 2104, 3224, 4776, 6784, 9408, 12672, 16776, 21736, 27792, 34944, 43488, 53400, 65032, 78336, 93720, 111112, 130976, 153216, 178360, 206272, 237552, 272024, 310368, 352360, 398752, 449280, 504776, 564928, 630648 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Diagonal of A190100.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-2) -2*a(n-3) +a(n-5) -3*a(n-6) +3*a(n-8) -a(n-9) +2*a(n-11) -2*a(n-12) -a(n-13) +a(n-14).
Empirical g.f.: 8*x^2*(2 + 2*x + 2*x^2 + 2*x^3 + x^4)*(1 + 2*x + 2*x^2 + 2*x^3 + 2*x^4) / ((1 - x)^5*(1 + x)^3*(1 + x^2)*(1 + x + x^2 + x^3 + x^4)). - Colin Barker, May 04 2018
EXAMPLE
Some solutions for n=5:
3 0 3 2 5 0 2 0 1 2 5 5 3 5 3 0 2 3 0 4
1 0 2 1 3 0 1 1 1 0 1 5 2 4 2 1 0 3 1 5
3 1 5 0 5 1 4 2 5 2 5 3 5 3 5 2 2 2 2 2
CROSSREFS
Cf. A190100.
Sequence in context: A266103 A100184 A304845 * A316542 A306057 A059165
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 04 2011
STATUS
approved

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Last modified July 20 22:01 EDT 2024. Contains 374459 sequences. (Running on oeis4.)