|
Search: id:A163841
|
|
|
| A163841 |
|
Triangle interpolating the swinging factorial (A056040) restricted to even indices with its binomial transform. Same as interpolating bilateral Schroeder paths (A026375) with the central binomial coefficients (A000984). |
|
+0 4
|
|
| 1, 3, 2, 11, 8, 6, 45, 34, 26, 20, 195, 150, 116, 90, 70, 873, 678, 528, 412, 322, 252, 3989, 3116, 2438, 1910, 1498, 1176, 924, 18483, 14494, 11378, 8940, 7030, 5532, 4356, 3432, 86515, 68032, 53538
(list; table; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
COMMENT
|
Triangle read by rows. For n >= 0, k >= 0 let
T(n,k) = sum{i=k..n} binomial(n-k,n-i)*(2i)$
where i$ denotes the swinging factorial of i (A056040).
|
|
REFERENCES
|
Peter Luschny, "Divide, swing and conquer the factorial and the lcm{1,2,...,n}", preprint, April 2008.
Tony D. Noe, On the Divisibility of Generalized Central Trinomial Coefficients, Journal of Integer Sequences, Vol. 9 (2006), Article 06.2.7.
|
|
LINKS
|
Peter Luschny, Swinging Factorial.
|
|
EXAMPLE
|
1
3, 2
11, 8, 6
45, 34, 26, 20
195, 150, 116, 90, 70
873, 678, 528, 412, 322, 252
3989, 3116, 2438, 1910, 1498, 1176, 924
|
|
MAPLE
|
Computes n rows of the triangle. For the functions 'SumTria' and 'swing' see A163840.
a := n -> SumTria(k->swing(2*k), n, true);
|
|
CROSSREFS
|
Sum rows are A163844. Cf. A056040, A163650, A163841, A163842, A163840, A026375, A002426, A000984.
Sequence in context: A013945 A065014 A072656 this_sequence A072634 A086194 A159610
Adjacent sequences: A163838 A163839 A163840 this_sequence A163842 A163843 A163844
|
|
KEYWORD
|
nonn,tabl
|
|
AUTHOR
|
Peter Luschny (peter(AT)luschny.de), Aug 06 2009
|
|
|
Search completed in 0.003 seconds
|