cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A154407 a(n) = 5*2^(n-1) + 3*6^n/2.

Original entry on oeis.org

4, 14, 64, 344, 1984, 11744, 70144, 420224, 2520064, 15117824, 90701824, 544200704, 3265183744, 19591061504, 117546287104, 705277558784, 4231665025024, 25389989494784, 152339935657984, 914039611326464, 5484237662715904
Offset: 0

Views

Author

Paul Curtz, Jan 09 2009

Keywords

Comments

One of the diagonals of the n-th differences of A154383.

Examples

			Sequence A154383 and its k-th iterated difference in the k-th row are
...1.....0.....4.....2.....16......8.....64.....32....256....128...1024.
..-1.....4....-2....14.....-8.....56....-32....224...-128....896...-512.
...5....-6....16...-22.....64....-88....256...-352...1024..-1408...4096.
.-11....22...-38....86...-152....344...-608...1376..-2432...5504..-9728.
..33...-60...124..-238....496...-952...1984..-3808...7936.-15232..31744.
.-93...184..-362...734..-1448...2936..-5792..11744.-23168..46976.-92672.
.277..-546..1096.-2182...4384..-8728..17536.-34912..70144.-139648.280576.
The sequence is the diagonal T(k,k+2) in this array.
		

Programs

Formula

a(n+1) = 6*a(n) - 10*2^n.
a(n) = 6*a(n) - 5*A020714(n+1).
G.f.: 2*(2 - 9*x)/((6*x-1)*(2*x-1)). - R. J. Mathar, May 21 2009
E.g.f.: (1/2)*( 5*exp(2*x) + 3*exp(6*x) ). - G. C. Greubel, Sep 16 2016

Extensions

Edited by R. J. Mathar, May 21 2009

A167784 a(n) = 2^n - (1 - (-1)^n)*3^((n-1)/2).

Original entry on oeis.org

1, 0, 4, 2, 16, 14, 64, 74, 256, 350, 1024, 1562, 4096, 6734, 16384, 28394, 65536, 117950, 262144, 484922, 1048576, 1979054, 4194304, 8034314, 16777216, 32491550, 67108864, 131029082, 268435456, 527304974, 1073741824, 2118785834, 4294967296, 8503841150
Offset: 0

Views

Author

Paul Curtz, Nov 12 2009

Keywords

Comments

Binomial transform of A077917, the signed variant of A127864.

Crossrefs

Programs

  • Maple
    seq(2^n - (1 - (-1)^n)*3^((n-1)/2), n=0..100); # Robert Israel, Apr 11 2019
  • Mathematica
    LinearRecurrence[{2, 3, -6}, {1, 0, 4}, 40] (* Harvey P. Dale, Nov 29 2011 *)

Formula

a(n) = A167936(n+1) - A167936(n).
a(2n) = A000302(n). a(2n+1) = 2*A005061(n).
a(n) = 2*a(n-1) + 3*a(n-2) - 6*a(n-3).
G.f.: (x-1)^2/((2*x-1)*(3*x^2-1)).
a(n+4) mod 9 = A153130(n+4) = A146501(n+2), n>=0.
E.g.f.: exp(2*x) - (2/sqrt(3))*sinh(sqrt(3)*x). - G. C. Greubel, Jun 27 2016

Extensions

Edited and extended by R. J. Mathar, Feb 27 2010
Incorrect b-file corrected by Robert Israel, Apr 11 2019
Showing 1-2 of 2 results.