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A123162 Triangle read by rows: binomial[2*n-1,2*m-1]. 1
1, 1, 1, 1, 3, 1, 1, 5, 10, 1, 1, 7, 35, 21, 1, 1, 9, 84, 126, 36, 1, 1, 11, 165, 462, 330, 55, 1, 1, 13, 286, 1287, 1716, 715, 78, 1, 1, 15, 455, 3003, 6435, 5005, 1365, 105, 1, 1, 17, 680, 6188, 19448, 24310, 12376, 2380, 136, 1, 1, 19, 969, 11628, 50388, 92378, 75582 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,5

COMMENTS

Column k has g.f. x^k*sum{j=0..k, C(2k,2j)*x^j}/(1-x)^(2k+0^k); - Paul Barry (pbarry(AT)wit.ie), May 26 2008

FORMULA

a(n,m) = If [n == m == 0 || m == 0, 1, (2*n - 1)!/((2*(n - m))!*(2*m - 1)!)]

a(n,k)=C(2n-1,2k-1)+0^n+0^k+0^(n+k); - Paul Barry (pbarry(AT)wit.ie), May 26 2008

EXAMPLE

1

1, 1

1, 3, 1

1, 5, 10, 1

1, 7, 35, 21, 1

1, 9, 84, 126, 36, 1

1, 11, 165, 462, 330, 55, 1

MATHEMATICA

t[n_, m_] = If [n == m == 0 || m == 0, 1, (2*n - 1)!/((2*(n - m))!*(2*m - 1)!)]; a = Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}]; Flatten[a]

CROSSREFS

Cf. A103327.

Sequence in context: A141523 A201588 A086385 * A083075 A195892 A195522

Adjacent sequences:  A123159 A123160 A123161 * A123163 A123164 A123165

KEYWORD

nonn,tabl

AUTHOR

Roger Bagula (rlbagulatftn(AT)yahoo.com), Oct 02 2006

EXTENSIONS

Edited by N. J. A. Sloane (njas(AT)research.att.com), Oct 04 2006

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Last modified February 16 09:56 EST 2012. Contains 205904 sequences.