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.

A094569 Associated with alternating row sums of array in A094568.

Original entry on oeis.org

2, 11, 78, 532, 3649, 25008, 171410, 1174859, 8052606, 55193380, 378301057, 2592914016, 17772097058, 121811765387, 834910260654, 5722560059188, 39223010153665, 268838511016464, 1842646566961586, 12629687457714635, 86565165637040862, 593326472001571396
Offset: 0

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Author

Clark Kimberling, May 12 2004

Keywords

Examples

			Obtain 11,78,532 from a(0)=2 and Fibonacci numbers 13,89,610: 11=13-2, 78=89-11, 532=610-78.
		

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{6,6,-1},{2,11,78},30] (* Harvey P. Dale, Feb 15 2025 *)
  • PARI
    Vec(-(x-2)/((x+1)*(x^2-7*x+1)) + O(x^100)) \\ Colin Barker, Nov 19 2014
    
  • PARI
    vector(30, n, n--;(fibonacci(4*n+5) + (-1)^n)/3) \\ Michel Marcus, Nov 19 2014

Formula

a(n) = F(4n+3) - a(n-1) for n >= 1, where a(0) = 2.
a(n) = (Fib(4n+5) + (-1)^n )/3. - Ralf Stephan, Dec 04 2004
a(n) = (-1)^n * sum((-1)^k*Fibonacci(4*k+3), k=0..n). - Gary Detlefs, Jan 22 2013
a(n) = 6*a(n-1) + 6*a(n-2) - a(n-3). - Colin Barker, Nov 19 2014
G.f.: -(x-2) / ((x+1)*(x^2-7*x+1)). - Colin Barker, Nov 19 2014

Extensions

More terms from Colin Barker, Nov 19 2014