The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A141478 Binomial(n+2,3)*4^3. 2
 64, 256, 640, 1280, 2240, 3584, 5376, 7680, 10560, 14080, 18304, 23296, 29120, 35840, 43520, 52224, 62016, 72960, 85120, 98560, 113344, 129536, 147200, 166400, 187200, 209664, 233856, 259840, 287680, 317440, 349184, 382976, 418880, 456960 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Number of n permutations (n>=3) of 5 objects u, v, z, x, y with repetition allowed, containing n-3 u's. Example: if n=3 then n-3 =zero (0) u, a(1)=64 if n=4 then n-3= one (1) u, a(2)=256 if n=5 then n-3= two (2) u, a(3)=640 etc... LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1). FORMULA G.f.:64*x/(1-x)^4. a(n)=32*n*(n+1)*(n+2)/3 = 64*A000292(n). a(n) = 4*a(n-1) -6*a(n-2) +4*a(n-3) -a(n-4). - Vincenzo Librandi, Jun 29 2012 MAPLE seq(binomial(n+2, 3)*4^3, n=1..36); MATHEMATICA CoefficientList[Series[64/(1-x)^4, {x, 0, 40}], x] (* Vincenzo Librandi, Jun 29 2012 *) PROG (MAGMA) [Binomial(n+2, 3)*4^3: n in [1..34]];  // Bruno Berselli, Apr 07 2011 (MAGMA) I:=[64, 256, 640, 1280]; [n le 4 select I[n] else 4*Self(n-1)-6*Self(n-2)+4*Self(n-3)-Self(n-4): n in [1..50]]; // Vincenzo Librandi, Jun 29 2012 CROSSREFS Cf. A035008, A038231 (3rd subdiagonal). Sequence in context: A236331 A321070 A017066 * A107262 A255662 A045029 Adjacent sequences:  A141475 A141476 A141477 * A141479 A141480 A141481 KEYWORD nonn,easy AUTHOR Zerinvary Lajos, Aug 09 2008 EXTENSIONS Offset adapted to the g.f and indexes in comment by Bruno Berselli, Apr 07 2011 STATUS approved

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

Last modified December 3 05:05 EST 2021. Contains 349445 sequences. (Running on oeis4.)