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A107430
Triangle read by rows: row n is row n of Pascal's triangle (A007318) sorted into increasing order.
12
1, 1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 4, 4, 6, 1, 1, 5, 5, 10, 10, 1, 1, 6, 6, 15, 15, 20, 1, 1, 7, 7, 21, 21, 35, 35, 1, 1, 8, 8, 28, 28, 56, 56, 70, 1, 1, 9, 9, 36, 36, 84, 84, 126, 126, 1, 1, 10, 10, 45, 45, 120, 120, 210, 210, 252, 1, 1, 11, 11, 55, 55, 165, 165, 330, 330, 462, 462, 1
OFFSET
0,6
COMMENTS
By rows, equals partial sums of A053121 reversed rows. Example: Row 4 of A053121 = (2, 0, 3, 0, 1) -> (1, 0, 3, 0, 2) -> (1, 1, 4, 4, 6). - Gary W. Adamson, Dec 28 2008, edited by Michel Marcus, Sep 22 2015
FORMULA
T(n,k) = C(n,floor(k/2)). - Paul Barry, Dec 15 2006; corrected by Philippe Deléham, Mar 15 2007
Sum_{k=0..n} T(n,k)*x^(n-k) = A127363(n), A127362(n), A127361(n), A126869(n), A001405(n), A000079(n), A127358(n), A127359(n), A127360(n) for x=-4,-3,-2,-1,0,1,2,3,4 respectively. - Philippe Deléham, Mar 29 2007
EXAMPLE
Triangle begins:
1;
1,1;
1,1,2;
1,1,3,3;
1,1,4,4,6;
MAPLE
for n from 0 to 10 do sort([seq(binomial(n, k), k=0..n)]) od; # yields sequence in triangular form. - Emeric Deutsch, May 28 2005
MATHEMATICA
Flatten[ Table[ Sort[ Table[ Binomial[n, k], {k, 0, n}]], {n, 0, 12}]] (* Robert G. Wilson v, May 28 2005 *)
PROG
(Haskell)
import Data.List (sort)
a107430 n k = a107430_tabl !! n !! k
a107430_row n = a107430_tabl !! n
a107430_tabl = map sort a007318_tabl
-- Reinhard Zumkeller, May 26 2013
(Magma) /* As triangle */ [[Binomial(n, Floor(k/2)) : k in [0..n]]: n in [0.. 15]]; // Vincenzo Librandi, Sep 22 2015
(PARI) for(n=0, 20, for(k=0, n, print1(binomial(n, floor(k/2)), ", "))) \\ G. C. Greubel, May 22 2017
CROSSREFS
A061554 is similar but with rows sorted into decreasing order.
Cf. A034868.
Cf. A053121. - Gary W. Adamson, Dec 28 2008
Cf. A103284.
Sequence in context: A176427 A324592 A099573 * A330885 A355146 A255741
KEYWORD
nonn,tabl,easy
AUTHOR
Philippe Deléham, May 21 2005
EXTENSIONS
More terms from Emeric Deutsch and Robert G. Wilson v, May 28 2005
STATUS
approved