login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A140229 Binomial transform of [1, 3, 3, 1, -2, 3, -4, 5, ...]. 2
1, 4, 10, 20, 33, 49, 68, 90, 115, 143, 174, 208, 245, 285, 328, 374, 423, 475, 530, 588, 649, 713, 780, 850, 923, 999, 1078, 1160, 1245, 1333, 1424, 1518, 1615, 1715, 1818, 1924, 2033, 2145, 2260, 2378, 2499, 2623, 2750, 2880, 3013, 3149, 3288, 3430, 3575 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
The falling diagonal starting with T(1,4) in A049777 (as a square array) gives the terms of this sequence for n >=3. - Bob Selcoe, Oct 27 2014
LINKS
FORMULA
A007318 * [1, 3, 3, 1, -2, 3, -4, 5,...].
a(n) = (n+1)(3n-4)/2, for n>=3. - Emeric Deutsch, May 18 2008
G.f.: x(1+x+x^2+x^3-x^4)/(1-x)^3. a(n) = 3*a(n-1) -3*a(n-2) + a(n-3), n>5. a(n+1)-a(n) = A016777(n), n>3. - R. J. Mathar, Nov 25 2008
EXAMPLE
a(5) = 33 = (1, 4, 6, 4, 1) dot (1, 3, 3, 1, -2) = (1 + 12 + 18 + 4 - 2).
MAPLE
1, 4, seq((1/2)*(n+1)*(3*n-4), n=3..40); # Emeric Deutsch, May 18 2008
MATHEMATICA
s=-2; lst={1, 4}; Do[s+=n+1; If[n>3, AppendTo[lst, s]], {n, 0, 6!, 3}]; lst (* Vladimir Joseph Stephan Orlovsky, Oct 25 2008 *)
PROG
(Magma) [1, 4] cat [(n+1)*(3*n-4)/2: n in [3..50]]; // Vincenzo Librandi, Oct 27 2014
CROSSREFS
Sequence in context: A008039 A024986 A028358 * A100440 A027373 A008142
KEYWORD
nonn
AUTHOR
Gary W. Adamson, May 13 2008
EXTENSIONS
More terms from Emeric Deutsch, May 18 2008
More terms from Vladimir Joseph Stephan Orlovsky, Oct 25 2008
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 29 03:51 EDT 2024. Contains 371264 sequences. (Running on oeis4.)