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.

A343043 a(n) = A343042(n, n).

Original entry on oeis.org

0, 1, 6, 9, 12, 15, 120, 127, 150, 153, 156, 159, 240, 247, 270, 273, 300, 303, 360, 367, 390, 393, 420, 423, 5040, 5065, 5166, 5193, 5172, 5199, 5880, 5911, 5910, 5913, 5916, 5919, 6000, 6031, 6030, 6033, 6060, 6063, 6120, 6151, 6150, 6153, 6180, 6183, 10080
Offset: 0

Views

Author

Rémy Sigrist, Apr 05 2021

Keywords

Comments

This sequence has similarities with A087019 and A343047.

Examples

			For n = 42:
- the factorial base representation of 42 is "1300", so:
              1 3 0 0
            x 1 3 0 0
            ---------
              0 0 0 0
            0 0 0 0
          1 3 0 0
      + 1 1 0 0
      ---------------
        1 1 3 0 0 0 0
- hence a(42) = 7! + 6! + 3*5! = 6120.
		

Crossrefs

Programs

  • PARI
    See Links section.

Formula

a(k!) = (2*k-1)! for any k > 0.
a(A007489(k)) = A007489(2*k-1) for any k > 0.