|
Search: id:A131086
|
|
|
| A131086 |
|
Triangle read by rows: T(n,k)=2*binom(n,k)-(-1)^(n-k) (0<=k<=n). |
|
+0 2
|
|
| 1, 3, 1, 1, 5, 1, 3, 5, 7, 1, 1, 9, 11, 9, 1, 3, 9, 21, 19, 11, 1, 1, 13, 29, 41, 29, 13, 1, 3, 13, 43, 69, 71, 41, 15, 1, 1, 17, 55, 113, 139, 113, 55, 17, 1, 3, 17, 73, 167, 253, 251, 169, 71, 19, 1, 1, 21, 89, 241, 419, 505, 419, 241, 89, 21, 1, 3, 21, 111, 329
(list; table; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
COMMENT
|
Row sums = A051049 starting (1, 4, 7, 16, 31, 64,...).
|
|
FORMULA
|
G.f.=G(t,z)=(1+3z-tz-2tz^2)/[(1+z)(1-tz)(1-z-tz)]. - Emeric Deutsch (deutsch(AT)duke.poly.edu), Jun 21 2007
|
|
EXAMPLE
|
First few rows of the triangle are:
1;
3, 1;
1, 5, 1;
3, 5, 7, 1;
1, 9, 11, 9, 1;
3, 9, 21, 19, 11, 1;
1, 13, 29, 41, 29, 13, 1;
...
|
|
MAPLE
|
T := proc (n, k) if k <= n then 2*binomial(n, k)-(-1)^(n-k) else 0 end if end proc: for n from 0 to 11 do seq(T(n, k), k = 0 .. n) end do; # yields sequence in triangular form - Emeric Deutsch (deutsch(AT)duke.poly.edu), Jun 21 2007
|
|
CROSSREFS
|
Cf. A000012, A051049.
Sequence in context: A046230 A046229 A124738 this_sequence A069002 A076334 A014475
Adjacent sequences: A131083 A131084 A131085 this_sequence A131087 A131088 A131089
|
|
KEYWORD
|
nonn,tabl
|
|
AUTHOR
|
Gary W. Adamson (qntmpkt(AT)yahoo.com), Jun 14 2007
|
|
EXTENSIONS
|
More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Jun 21 2007
Sequence corrected by njas, Sep 30 2007
|
|
|
Search completed in 0.002 seconds
|