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A129855 A symmetrical triangle of coefficients based on A000217: a(n) = Binomial[n + 2, 2]; t(n,m)=a(n - m + 1)*a(m + 1). 0
9, 18, 18, 30, 36, 30, 45, 60, 60, 45, 63, 90, 100, 90, 63, 84, 126, 150, 150, 126, 84, 108, 168, 210, 225, 210, 168, 108, 135, 216, 280, 315, 315, 280, 216, 135, 165, 270, 360, 420, 441, 420, 360, 270, 165, 198, 330, 450, 540, 588, 588, 540, 450, 330, 198, 234 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Row sums are:

{9, 36, 96, 210, 406, 720, 1197, 1892, 2871, 4212, 6006}.

REFERENCES

G. E. Andrews, Number Theory, 1971, Dover Publications New York, p 44.

FORMULA

a(n) = Binomial[n + 2, 2]; t(n,m)=a(n - m + 1)*a(m + 1).

EXAMPLE

{9},

{18, 18},

{30, 36, 30},

{45, 60, 60, 45},

{63, 90, 100, 90, 63},

{84, 126, 150, 150, 126, 84},

{108, 168, 210, 225, 210, 168, 108},

{135, 216, 280, 315, 315, 280, 216, 135},

{165, 270, 360, 420, 441, 420, 360, 270, 165},

{198, 330, 450, 540, 588, 588, 540, 450, 330, 198},

{234, 396, 550, 675, 756, 784, 756, 675, 550, 396, 234}

MATHEMATICA

Clear[a, n, m, t] (*A000217*) a[0] = 1; a[1] = 3; a[n_] := a[n] = Binomial[n + 2, 2]; Table[a[n], {n, 0, 30}]; t[n_, m_] = a[n - m + 1]*a[m + 1]; Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}]; Flatten[%]

CROSSREFS

Cf. A000217.

Sequence in context: A046125 A040072 A034728 * A158908 A202188 A060993

Adjacent sequences:  A129852 A129853 A129854 * A129856 A129857 A129858

KEYWORD

nonn,tabl

AUTHOR

Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Aug 25 2008

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Last modified February 14 17:34 EST 2012. Contains 205644 sequences.