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A157694
Triangle read by rows: the Pascal triangle A007318 with all elements replaced by 1 which do not equal the central binomial coefficients.
0
1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 1, 6, 1, 1, 1, 1, 10, 10, 1, 1, 1, 1, 1, 20, 1, 1, 1, 1, 1, 1, 35, 35, 1, 1, 1, 1, 1, 1, 1, 70, 1, 1, 1, 1, 1, 1, 1, 1, 126, 126, 1, 1, 1, 1, 1, 1, 1, 1, 1, 252, 1, 1, 1, 1, 1
OFFSET
0,5
COMMENTS
Row sums are {1, 2, 4, 8, 10, 24, 26, 76, 78, 260, 262,...}.
FORMULA
t(n,m)= binomial(n,[n/2]) if this equals binomial(n,m), else 1.
EXAMPLE
{1},
{1, 1},
{1, 2, 1},
{1, 3, 3, 1},
{1, 1, 6, 1, 1},
{1, 1, 10, 10, 1, 1},
{1, 1, 1, 20, 1, 1, 1},
{1, 1, 1, 35, 35, 1, 1, 1},
{1, 1, 1, 1, 70, 1, 1, 1, 1},
{1, 1, 1, 1, 126, 126, 1, 1, 1, 1},
{1, 1, 1, 1, 1, 252, 1, 1, 1, 1, 1}
MATHEMATICA
Clear[t, n, m];
t[n_, m_] = If[ Binomial[n, m] == Binomial[n, Floor[n/2]], Binomial[n, Floor[n/2]], 1];
Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}];
Flatten[%]
CROSSREFS
Sequence in context: A026082 A117185 A129181 * A271187 A093557 A098802
KEYWORD
nonn,easy,tabl
AUTHOR
Roger L. Bagula, Mar 04 2009
EXTENSIONS
Edited by the Associate Editors of the OEIS, Apr 10 2009
STATUS
approved