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A172279
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Triangle, read by rows: T(n, k) = ceiling( binomial(n, k)/(1 + (k - floor(n/2))^2) ).
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2
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1, 1, 1, 1, 2, 1, 1, 3, 2, 1, 1, 2, 6, 2, 1, 1, 3, 10, 5, 1, 1, 1, 2, 8, 20, 8, 2, 1, 1, 2, 11, 35, 18, 5, 1, 1, 1, 1, 6, 28, 70, 28, 6, 1, 1, 1, 1, 8, 42, 126, 63, 17, 4, 1, 1, 1, 1, 5, 24, 105, 252, 105, 24, 5, 1, 1, 1, 1, 6, 33, 165, 462, 231, 66, 17, 4, 1, 1, 1, 1, 4, 22, 99, 396, 924, 396, 99, 22, 4, 1, 1
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OFFSET
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0,5
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COMMENTS
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Row sums are: {1, 2, 4, 7, 12, 21, 42, 74, 142, 264, 524, ...}.
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LINKS
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G. C. Greubel, Rows n = 0..100 of triangle, flattened
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FORMULA
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T(n, k) = ceiling( binomial(n, k)/((1 + (k - floor(n/2))^2)).
T(2*n, n) = binomial(2*n,n) (cf. A000984). - Michel Marcus, May 22 2019
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EXAMPLE
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Triangle begins as:
1;
1, 1;
1, 2, 1;
1, 3, 2, 1;
1, 2, 6, 2, 1;
1, 3, 10, 5, 1, 1;
1, 2, 8, 20, 8, 2, 1;
1, 2, 11, 35, 18, 5, 1, 1;
1, 1, 6, 28, 70, 28, 6, 1, 1;
1, 1, 8, 42, 126, 63, 17, 4, 1, 1;
1, 1, 5, 24, 105, 252, 105, 24, 5, 1, 1;
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MATHEMATICA
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T[n_, k_]:= Ceiling[Binomial[n, k]/(1+(k-Floor[n/2])^2)];
Table[T[n, k], {n, 0, 12}, {k, 0, n}]//Flatten
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PROG
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(PARI)
{T(n, k) = ceil(binomial(n, k)/(1 + (k -floor(n/2))^2))};
for(n=0, 12, for(k=0, n, print1(T(n, k), ", "))) \\ G. C. Greubel, May 21 2019
(Magma)
T:= func< n, k | Ceiling(Binomial(n, k)/(1 + (k - Floor(n/2))^2)) >;
[[T(n, k) : k in [0..n]]: n in [0..12]]; // G. C. Greubel, May 21 2019
(Sage)
def T(n, k): return ceil(binomial(n, k)/(1 + (k -floor(n/2))^2))
[[T(n, k) for k in (0..n)] for n in (0..12)] # G. C. Greubel, May 21 2019
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CROSSREFS
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Cf. A000984 (central binomial coefficients).
Sequence in context: A006375 A327520 A184441 * A348285 A164953 A136622
Adjacent sequences: A172276 A172277 A172278 * A172280 A172281 A172282
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KEYWORD
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nonn,tabl
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AUTHOR
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Roger L. Bagula, Jan 30 2010
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EXTENSIONS
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Edited by G. C. Greubel, May 21 2019
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STATUS
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approved
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