Average of all $a_n$ where $a_0$=1, $a_{n+1}=\omega^{a_n}$, and $\omega=\frac{\pi i}{\ln(2)}$

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Essentially, I've noticed that tetrations of $\omega=\frac{\pi i}{\ln(2)}$ seem to converge on a cycle of three fixed points. Specifically, if $a_0$=1, and $a_{n+1}=\omega^{a_n}$, then we find

$$n\equiv 0\mod 3\implies a_n\approx 1$$ $$n\equiv 1\mod 3\implies a_n\approx \omega$$ $$n\equiv 2\mod 3\implies a_n\approx 0$$

for sufficently large $n$. Thus,

$$\lim_{k\to\infty}\frac{1}{k}\sum_{n=0}^{k-1} a_n\approx\frac{\omega+1}{3}$$

This is a sloppy approximation, however, according to my numerical approximations up to $k=1000$ with $512$-bit precision, the real and imaginary parts are only off by about $1.6\%$ and $0.059\%$, respectively.

Regardless, I am curious as to how I would go about deducing the exact values of the 3-cycle, and consequently, the average.

I'm stuck somewhere between knowing if this is trivially done algebraically or beyond my abilities. Hence, any insight would be greatly appreciated.

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Hmm, the sequence $$\small {[1,\omega,\omega^\omega,...] = \\ [1 , 4.532360142\,î , 0.0006829063+0.0004341759\,î , 1.0003486+0.001729456\,î , \ldots]}$$ converges to a set of 3-periodic points (read columnwise then rowwise):

                                                 1                           4.5323601418271938096*I  0.00068290635422801001329+0.00043417595543682445347*I
  1.0003486016012257041+0.0017294564858244654813*I  -0.014296381361689355118+4.5224234314465601333*I  0.00069451584490774680341+0.00040584518415648376190*I
  1.0004107139950798728+0.0017049751728907727363*I  -0.014572226797463840409+4.5230210131221537637*I  0.00069338455088690143099+0.00040562120667642269269*I
  1.0004093592060316620+0.0017028564749635603501*I  -0.014548137885828186729+4.5230268830372496621*I  0.00069338445224534295552+0.00040566462131440903552*I
  1.0004092907219684738+0.0017029218404862040133*I  -0.014548095122955727375+4.5230259506438771257*I  0.00069338605694908410488+0.00040566431121234439216*I
  1.0004092936318701483+0.0017029238983085678873*I  -0.014548129880057088489+4.5230259558021323495*I  0.00069338603389526427805+0.00040566425416620319253*I
  1.0004092936868689919+0.0017029237759283003772*I  -0.014548129438299196098+4.5230259570489862191*I  0.00069338603195424966201+0.00040566425543020613696*I
  1.0004092936819500823+0.0017029237747807346308*I  -0.014548129395425578656+4.5230259570236543595*I  0.00069338603201497662259+0.00040566425549278394913*I
  1.0004092936819432323+0.0017029237749707612258*I  -0.014548129396671324148+4.5230259570222534240*I  0.00069338603201684975438+0.00040566425549008810308*I
  1.0004092936819503025+0.0017029237749696410250*I  -0.014548129396714080210+4.5230259570223095734*I  0.00069338603201673661730+0.00040566425549003838086*I
  1.0004092936819502100+0.0017029237749693879057*I  -0.014548129396711696734+4.5230259570223107473*I  0.00069338603201673559789+0.00040566425549004292014*I
  1.0004092936819502013+0.0017029237749693931517*I  -0.014548129396711670588+4.5230259570223106507*I  0.00069338603201673577296+0.00040566425549004292500*I
  1.0004092936819502016+0.0017029237749693934346*I  -0.014548129396711674344+4.5230259570223106505*I  0.00069338603201673577187+0.00040566425549004291850*I
  1.0004092936819502016+0.0017029237749693934231*I  -0.014548129396711674327+4.5230259570223106506*I  0.00069338603201673577164+0.00040566425549004291859*I
  1.0004092936819502016+0.0017029237749693934229*I  -0.014548129396711674322+4.5230259570223106506*I  0.00069338603201673577165+0.00040566425549004291859*I
  1.0004092936819502016+0.0017029237749693934229*I  -0.014548129396711674322+4.5230259570223106506*I  0.00069338603201673577165+0.00040566425549004291859*I
  1.0004092936819502016+0.0017029237749693934229*I  -0.014548129396711674322+4.5230259570223106506*I  0.00069338603201673577165+0.00040566425549004291859*I
  1.0004092936819502016+0.0017029237749693934229*I  -0.014548129396711674322+4.5230259570223106506*I  0.00069338603201673577165+0.00040566425549004291859*I
  1.0004092936819502016+0.0017029237749693934229*I  -0.014548129396711674322+4.5230259570223106506*I  0.00069338603201673577165+0.00040566425549004291859*I
  1.0004092936819502016+0.0017029237749693934229*I  -0.014548129396711674322+4.5230259570223106506*I  0.00069338603201673577165+0.00040566425549004291859*I
   ... ... ...

The convergence is rather fast:(showing the rowwise differences = differences between $a_{n+3}$ and $a_n$)

                                            1                                 4.532360142*I             0.0006829063542+0.0004341759554*I
             0.0003486016012+0.001729456486*I               -0.01429638136-0.009936710381*I           0.00001160949068-0.00002833077128*I
          0.00006211239385-0.00002448131293*I            -0.0002758454358+0.0005975816756*I       -0.000001131294021-0.0000002239774801*I
       -0.000001354789048-0.000002118697927*I          0.00002408891164+0.000005869915096*I        -9.864155848E-11+0.00000004341463799*I
   -0.00000006848406319+0.00000006536552264*I      0.00000004276287246-0.0000009323933725*I  0.000000001604703741-0.0000000003101020646*I
  0.000000002909901674+0.000000002057822364*I   -0.00000003475710136+0.000000005158255224*I            -2.305381983E-11-5.704614120E-11*I
            5.499884363E-11-1.223802675E-10*I  0.0000000004417578924+0.000000001246853870*I            -1.941014616E-12+1.264002944E-12*I
           -4.918909647E-12-1.147565746E-12*I             4.287361744E-11-2.533185956E-11*I             6.072696058E-14+6.257781217E-14*I
           -6.849972637E-15+1.900265950E-13*I            -1.245745492E-12-1.400935516E-12*I             1.873131785E-15-2.695846045E-15*I
            7.070201133E-15-1.120200834E-15*I            -4.275606224E-14+5.614939416E-14*I            -1.131370763E-16-4.972221707E-17*I
           -9.248153225E-17-2.531192973E-16*I             2.383476585E-15+1.173881015E-15*I            -1.019414635E-18+4.539278918E-18*I
           -8.683369712E-18+5.246046361E-18*I             2.614521192E-17-9.654298828E-17*I             1.750746883E-19+4.858823331E-21*I
            2.565724890E-19+2.829026661E-19*I            -3.755810234E-18-2.682633641E-19*I            -1.085711545E-21-6.503400345E-21*I
            8.597894125E-21-1.152376721E-20*I             1.723116391E-20+1.407003563E-19*I            -2.324275952E-22+8.711115492E-23*I
           -4.878906368E-22-2.343770336E-22*I             5.073771411E-21-1.653429860E-21*I             4.898098865E-24+7.957707265E-24*I
           -5.133388691E-24+1.971933378E-23*I            -9.775439864E-23-1.755059387E-22*I             2.586069729E-25-2.384730683E-25*I
            7.656457830E-25+4.715036720E-26*I            -5.777770819E-24+4.879962887E-24*I            -1.067948890E-26-7.831068996E-27*I
           -3.791136794E-27-2.862819481E-26*I             2.220491132E-25+1.781983883E-25*I            -2.121474194E-28+4.511563690E-28*I
           -1.030295889E-27+3.469563090E-28*I             4.978996047E-27-9.491597017E-27*I             1.820150592E-29+4.577566455E-30*I
            2.026431715E-29+3.555780389E-29*I            -3.866573860E-28-1.153597268E-28*I             3.758402816E-32-7.055515103E-31*I

and the rowwise sums $a_{3n}+a_{3n+1}+a_{3n+2}$:

   1.000682906+4.532794318*I
  0.9867467361+4.524558733*I
  0.9865318717+4.525131610*I
  0.9865546058+4.525135404*I
  0.9865545817+4.525134537*I
  0.9865545498+4.525134544*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I
  0.9865545503+4.525134545*I

update In the end, your sum should converge to the sum of your three values $(a_1 +a_2+a_3)/3$ and just for visualization I've printed the partial averages when $n$ is increased for the sum.

Mat(vectorv(20,j,[n=2^j,1/n* (   ((n-1)\3+1)*a[1]+ ((n-2)\3+1)*a[2]+((n-3)\3+1)*a[3]) ]))        

     n    partial average (up to n)
----------------------------------------------------
[      2 0.492930582143 + 2.26236444040*I]
[      4 0.496740961000 + 1.13170936721*I]
[      8 0.369871283115 + 1.69687474636*I]
[     16 0.370823877829 + 1.41421097806*I]
[     32 0.339106458358 + 1.55550232285*I]
[     64 0.339344607037 + 1.48483638078*I]
[    128 0.331415252169 + 1.52015921698*I]
[    256 0.331474789338 + 1.50249273146*I]
[    512 0.329492450622 + 1.51132344051*I]
[   1024 0.329507334914 + 1.50690681913*I]
[   2048 0.329011750235 + 1.50911449639*I]
[   4096 0.329015471308 + 1.50801034105*I]
[   8192 0.328891575138 + 1.50856226036*I]
[  16384 0.328892505406 + 1.50828622152*I]
[  32768 0.328861531364 + 1.50842420135*I]
[  65536 0.328861763931 + 1.50835519164*I]
[ 131072 0.328854020420 + 1.50838968660*I]
[ 262144 0.328854078562 + 1.50837243417*I]
[ 524288 0.328852142684 + 1.50838105791*I]
[1048576 0.328852157220 + 1.50837674481*I]
   ...    ...

This converges obviously, and to what? See

(a[1]+a[2]+a[3])/3
%1893 = 0.328851516772 + 1.50837818168*I

The value that you propose is $\large {{\pi\; î \over \ln 2 }+1 \over 3} \approx \frac13 + 1.51078671394 \; î $ and is a bit off.