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.

A045995 Rows of Fibonacci-Pascal triangle.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 3, 8, 3, 1, 1, 5, 55, 55, 5, 1, 1, 8, 610, 6765, 610, 8, 1, 1, 13, 10946, 9227465, 9227465, 10946, 13, 1, 1, 21, 317811, 225851433717, 190392490709135, 225851433717, 317811, 21, 1, 1, 34, 14930352
Offset: 0

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Author

Keywords

Examples

			1,
1,  1,
1,  1,      1,
1,  2,      2,            1,
1,  3,      8,            3,               1,
1,  5,     55,           55,               5,            1,
1,  8,    610,         6765,             610,            8,      1,
1, 13,  10946,      9227465,         9227465,        10946,     13,  1,
1, 21, 317811, 225851433717, 190392490709135, 225851433717, 317811, 21, 1,
...
		

Crossrefs

Cf. A000045, A007318, A006449 (row sums), A081667.
Main diagonal gives A281450.

Programs

  • Haskell
    a045995 n k = a045995_tabl !! n !! k
    a045995_row n = a045995_tabl !! n
    a045995_tabl = map (map (a000045 . fromInteger)) a007318_tabl
    -- Reinhard Zumkeller, Dec 29 2011
  • Maple
    A045995 := proc(n,k)
        combinat[fibonacci](binomial(n,k)) ;
    end proc: # R. J. Mathar, Dec 03 2014
  • Mathematica
    Flatten[Table[Fibonacci[Binomial[n,k]],{n,0,10},{k,0,n}]] (* Harvey P. Dale, Dec 31 2013 *)

Formula

Take Pascal triangle (A007318) and replace each i by Fibonacci(i): a(n,k)=Fibonacci(binomial(n,k)).

Extensions

More terms from David W. Wilson

A273397 a(n) = Fibonacci(Catalan(n)).

Original entry on oeis.org

1, 1, 1, 5, 377, 267914296, 1725375039079340637797070384, 202401005213503038261932567177107618332887918916819829782797456368284639448671475316218754
Offset: 0

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Author

Waldemar Puszkarz, May 21 2016

Keywords

Comments

Next term, a(8), which has 299 digits, is too large to include. Counterpart to A273398.
The number of digits of a(n) grows faster than Fibonacci(n), in contrast to A273398, and faster than Catalan(n-2), but slower than Catalan(n-1) or Catalan(n).

Examples

			For n = 3, a(3) = Fibonacci(Catalan(3)) = Fibonacci(5) = 5.
		

Crossrefs

Cf. A000045 (Fibonacci), A000108(Catalan), A263986, A273398 (related sequences with Fibonacci and Catalan numbers), A281450.

Programs

  • Maple
    a:= n-> (<<0|1>, <1|1>>^(binomial(2*n, n)/(n+1)))[1, 2]:
    seq(a(n), n=0..8);  # Alois P. Heinz, Jan 20 2017
  • Mathematica
    Fibonacci[CatalanNumber[Range[0, 7]]]
  • PARI
    for(n=0,7, cn=binomial(2*n, n)/(n+1); print1(fibonacci(cn) ","))

Formula

a(n) = A000045(A000108(n)).
Showing 1-2 of 2 results.