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.

A346434 Triangle read by rows of numbers with n 1's and n 0's in their representation in base of Fibonacci numbers (A210619), written as those 1's and 0's.

Original entry on oeis.org

10, 1001, 1010, 100101, 101001, 101010, 10010101, 10100101, 10101001, 10101010, 1001010101, 1010010101, 1010100101, 1010101001, 1010101010, 100101010101, 101001010101, 101010010101, 101010100101, 101010101001, 101010101010
Offset: 1

Views

Author

Kevin Ryde, Jul 18 2021

Keywords

Comments

The digits of T(n,k) are k pairs 10 followed by n-k pairs 01.

Examples

			Triangle begins:
        k=1       k=2       k=3       k=4
  n=1:  10
  n=2:  1001,     1010,
  n=3:  100101,   101001,   101010,
  n=4:  10010101, 10100101, 10101001, 10101010
  ...
For n=5,k=3, the 10 and 01 digit pairs are
           vvvvvv          k  = 3 pairs 10
  T(5,3) = 1010100101
                 ^^^^     n-k = 2 pairs 01
		

Crossrefs

Cf. A210619, A163662 (main diagonal), A014417 (Zeckendorf digits).

Programs

  • PARI
    T(n,k) = (10*100^n - 9*100^(n-k)) \ 99;

Formula

T(n,k) = (10*100^n - 9*100^(n-k) - 1)/99, for n>=1 and 1 <= k <= n.
T(n,k) = A014417(A210619(n,k)).
T(n,n) = A163662(n).
G.f.: x*y*(10 - 9*x - 100*x^2*y) / ((1-x) * (1-100*x) * (1-x*y) * (1-100*x*y) ).