login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A108039 Replace each entry 2^i(2j+1) of the triangle in A008280 with i and replace 0's with *'s; then the entries n in the new triangle do not occur beyond diagonal a(n), measured from the left edge and taking the left edge to be diagonal number 1. 0
2, 4, 4, 4, 8, 8, 8, 8, 10, 12, 12, 16, 16, 16, 16, 16, 18, 20 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..17.

V. I. Arnold, Bernoulli-Euler updown numbers associated with function singularities, their combinatorics and arithmetics, Duke Math. J. 63 (1991), 537-555.

Sanjay Ramassamy, Modular periodicity of the Euler numbers and a sequence by Arnold, arXiv:1712.08666 [math.CO], 2017.

EXAMPLE

3's do not occur beyond the 4th diagonal, so a(3) = 4.

Triangle begins:

       *

      * 0

     0 0 *

    * 0 1 1

   0 0 2 1 *

  * 0 1 1 4 4

CROSSREFS

Cf. A008280.

Sequence in context: A225355 A117726 A172307 * A103228 A076340 A076345

Adjacent sequences:  A108036 A108037 A108038 * A108040 A108041 A108042

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Jun 01 2005

EXTENSIONS

Corrected and extended by Sanjay Ramassamy, Nov 03 2018

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 23 18:13 EDT 2019. Contains 321433 sequences. (Running on oeis4.)