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A123539
Irregular triangle t(n,m) = binomial(n-m, n-binomial(m, floor(m/2))), read by rows, 0 <= m <= n/2.
2
0, 1, 2, 1, 3, 1, 4, 1, 1, 5, 1, 1, 6, 1, 1, 1, 7, 1, 1, 1, 8, 1, 1, 1, 6, 9, 1, 1, 1, 10, 10, 1, 1, 1, 15, 1, 11, 1, 1, 1, 21, 6, 12, 1, 1, 1, 28, 21, 0, 13, 1, 1, 1, 36, 56, 0, 14, 1, 1, 1, 45, 126, 0, 0, 15, 1, 1, 1, 55, 252, 0, 0
OFFSET
0,3
REFERENCES
F. R. K. Chung and R. L. Graham, Erdos on Graphs, AK Peters Ltd., Ma, 1998, page 90
EXAMPLE
The triangle starts:
0;
1;
2, 1;
3, 1;
4, 1, 1;
5, 1, 1;
6, 1, 1, 1;
7, 1, 1, 1;
8, 1, 1, 1, 6;
9, 1, 1, 1, 10;
10, 1, 1, 1, 15, 1;
MAPLE
A123539 := proc(n, m)
binomial(n-m, n-binomial(m, floor(m/2))) ;
end proc: # R. J. Mathar, May 12 2013
MATHEMATICA
t[n_, m_] := Binomial[n - m, n - Binomial[m, Floor[m/2]]] a0 = Table[Table[t[n, m], {m, 0, Floor[n/2]}], {n, 0, 10}] Flatten[a0]
CROSSREFS
Cf. A001405.
Sequence in context: A195839 A195838 A195837 * A142593 A360285 A226248
KEYWORD
nonn,tabf
AUTHOR
Roger L. Bagula, Nov 11 2006
STATUS
approved