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A190102 Number of 1:3:sqrt(10) proportioned triangles on a (n+1)X(n+1) grid 1
0, 0, 24, 80, 168, 344, 624, 1008, 1584, 2368, 3360, 4704, 6384, 8408, 10984, 14064, 17664, 22056, 27152, 32976, 39888, 47736, 56544, 66776, 78216, 90888, 105360, 121344, 138864, 158616, 180216, 203688, 229856, 258248, 288888, 322728, 359200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Diagonal of A190103

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..99

FORMULA

Empirical: a(n) = a(n-1) +2*a(n-3) -2*a(n-4) -a(n-6) +a(n-7) +a(n-9) -a(n-11) -2*a(n-12) +2*a(n-14) +a(n-15) -a(n-17) -a(n-19) +a(n-20) +2*a(n-22) -2*a(n-23) -a(n-25) +a(n-26)

EXAMPLE

Some solutions for n=5

..5..3....1..2....3..0....4..5....1..1....1..4....3..1....5..3....0..2....2..4

..2..0....1..5....3..3....3..5....1..4....2..5....0..4....2..3....0..1....1..4

..4..4....2..2....4..0....4..2....2..1....4..1....2..0....5..2....3..2....2..1

CROSSREFS

Sequence in context: A143839 A114818 A068379 * A060673 A167561 A211575

Adjacent sequences:  A190099 A190100 A190101 * A190103 A190104 A190105

KEYWORD

nonn

AUTHOR

R. H. Hardin May 04 2011

STATUS

approved

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Last modified February 25 23:44 EST 2020. Contains 332270 sequences. (Running on oeis4.)