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.

A127232 Eulerian numbers A000295 appearing in the intersection of Fibonacci and Lucas sequences A124168 and A127208.

Original entry on oeis.org

1, 120, 524268, 140737488355280, 2596148429267413814265248164609936, 57896044618658097711785492504343953926634992332820282019728792003956564819712
Offset: 1

Views

Author

T. D. Noe, Jan 09 2007

Keywords

Comments

a(n) is common to the r-step Fibonacci sequence and the s-step Lucas sequence for s=A001792(n)-2 and r=s-n+1. See A127208 for more information about the intersection of Fibonacci and Lucas sequences.

Examples

			a(2)=120 appears in the 5-step Fibonacci sequence A001591 and the 6-step Lucas sequence A074584. a(3)=524268 appears in the 16-step Fibonacci sequence and the 18-step Lucas sequence.
		

Crossrefs

Programs

  • Magma
    [2^((n+2)*2^(n-1)-1)-(n+2)*2^(n-1): n in [1..7]]; // Vincenzo Librandi, Aug 26 2011
    
  • PARI
    a(n) = my(k=(n+2)*2^(n-1)); 2^(k-1)-k; \\ Michel Marcus, Mar 25 2016

Formula

a(n) = 2^(k-1)-k for k=A001792(n).