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A141418 A triangular sequence of coefficients of Dynkin diagram weights for the Cartan Groups D_n: t(n,m)=m*(2*n - m - 1)/2. 0
0, 1, 1, 2, 3, 3, 3, 5, 6, 6, 4, 7, 9, 10, 10, 5, 9, 12, 14, 15, 15, 6, 11, 15, 18, 20, 21, 21, 7, 13, 18, 22, 25, 27, 28, 28, 8, 15, 21, 26, 30, 33, 35, 36, 36, 9, 17, 24, 30, 35, 39, 42, 44, 45, 45 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,4

COMMENTS

Row sums are:

{0, 2, 8, 20, 40, 70, 112, 168, 240, 330};

Here all the weights are divided by two where they aren't in Cahn.

REFERENCES

R. N. Cahn, Semi-Simple Lie Algebras and Their Representations, Dover, NY, 2006, ISBN 0-486-44999-8, p. 139.

FORMULA

t(n,m)=m*(2*n - m - 1)/2.

EXAMPLE

{0},

{1, 1},

{2, 3, 3},

{3, 5, 6, 6},

{4, 7, 9, 10, 10},

{5, 9, 12, 14, 15, 15},

{6, 11, 15, 18, 20, 21, 21},

{7, 13, 18, 22, 25, 27, 28, 28},

{8, 15, 21, 26, 30, 33, 35, 36, 36},

{9, 17, 24, 30, 35, 39, 42, 44, 45, 45}

MATHEMATICA

Clear[T, n, m, a] T[n_, m_] = m*(2*n - m - 1)/2; a = Table[Table[T[n, m], {m, 1, n}], {n, 1, 10}]; Flatten[a]

CROSSREFS

Sequence in context: A145281 A151687 A160573 * A130499 A020910 A029065

Adjacent sequences:  A141415 A141416 A141417 * A141419 A141420 A141421

KEYWORD

nonn,uned,tabl

AUTHOR

Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Aug 05 2008

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Last modified February 16 03:44 EST 2012. Contains 205860 sequences.