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.

A343609 a(n) = floor(n/9).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10
Offset: 0

Views

Author

M. F. Hasler, May 19 2021

Keywords

Comments

Also: Nonnegative integers repeated 9 times (with natural offset 0).

Crossrefs

Cf. A004526 ([n/2]), A002264 ([n/3]), A002265 ([n/4]), A002266 ([n/5]), A152467 ([n/6]), A132270 ([(n-1)/7]), A132292 ([(n-1)/8]), A059995 ([n/10]), A344420 ([n/11]), A342696 ([n/12]).
Repunits A002275 = A343609 o A011557.

Programs

  • Maple
    A343609 := n -> iquo(n,9); # illustration: map( A343609, [$0..99] );
  • Mathematica
    A343609[n_] := Floor[n/9]
    a[n_] := Quotient[n, 9]; Array[a, 100, 0] (* Amiram Eldar, May 19 2021 *)
    LinearRecurrence[{1,0,0,0,0,0,0,0,1,-1},{0,0,0,0,0,0,0,0,0,1},100] (* Harvey P. Dale, Mar 01 2025 *)
  • PARI
    apply( A343609(n)=n\9, [0..99])

Formula

a(n) = A002264(A002264(n)).
a(n) = a(n-1) + a(n-9) - a(n-10), n > 9;
G.f.: x^9/(1 - x - x^9 + x^10).

A342696 a(n) = floor(n/12).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8
Offset: 0

Views

Author

Wesley Ivan Hurt, May 18 2021

Keywords

Comments

Agrees with A064459 for n < 144, but a(144) = 12 whereas A064459(144) = 13.

Crossrefs

Cf. A064459, A221912 (partial sums), A344420 (floor n/11).

Programs

  • Mathematica
    Floor[Range[0, 200]/12]

Formula

G.f.: x^12 / ( (1+x)*(1+x^2)*(x^4-x^2+1)*(x^2-x+1)*(1+x+x^2)*(x-1)^2 ). - R. J. Mathar, Jul 08 2021
a(n) = a(n-1) + a(n-12) - a(n-13). - Wesley Ivan Hurt, Oct 29 2022
Showing 1-2 of 2 results.