

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
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OFFSET

0,1


LINKS

Table of n, a(n) for n=0..17.
V. I. Arnold, BernoulliEuler updown numbers associated with function singularities, their combinatorics and arithmetics, Duke Math. J. 63 (1991), 537555.
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



