A261896 Consider the 2^n values of A162795(i)/i^2 for 2^n <= i < 2^(n+1); a(n) = value of i where this quantity is minimized.

3, 5, 11, 25, 43, 89, 179, 361, 727, 1459, 2921, 5843, 11689, 23383, 46769, 93543, 187093, 374193, 748391, 1496785, 2993575, 5987157, 11974321, 23948647, 47897299, 95794607, 191589221, 383178449, 766356903, 1532713827, 3065427663, 6130855333, 12261710675, 24523421357, 49046842723

Offset: 0

Author

Robert Price, Sep 05 2015

Keywords

• nonn

Comments

Sequence suggested by Omar E. Pol.

Note that all values in this sequence are odd and that a(n) is approximately 2*a(n-1).

References

• D. Applegate, O. E. Pol and N. J. A. Sloane, The toothpick sequence and other sequences from cellular automata, Congressus Numerantium, v. 206 (2010) 157-191.

Links

• D. Applegate, O. E. Pol and N. J. A. Sloane, The toothpick sequence and other sequences from cellular automata; also available at arXiv:1004.3036v2, [math.CO], 2010.
• Steven R. Finch, Toothpicks and Live Cells, July 21, 2015. [Cached copy, with permission of the author]
• N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS

Crossrefs

Cf. A139250, A147562, A162795, A170927, A195853, A260239, A261313, A261895.

Programs

Mathematica

T = 1; t[0] = 0; t[1] = 1; lst = {1};
Do[twon = 2^n; Tmin = 1; imin = 1;
    Do[If[i==twon, t[i]=twon,
                   t[i]=2*t[i-twon]+t[i-twon+1];
                   If[OddQ[i], T=T+t[i];
                               Ttest=T/(i*i)];
                               If[Ttest