The MRB constant =
∞
∑
n=1
n
(-1)
-1+
1
n
n

.From the vast universe of (dd), where dd is defined as follows:
In[]:=
TranscendentalRecognize[(num_)?NumericQ,(basis_)?VectorQ]:=Module[{lr,ans},lr=FindIntegerNullVector[Prepend[N[basis,Precision[num]],num]];​​ans=Rest[lr].basis/First[lr];​​Sign[N[ans]]*Sign[num]*ans]
S=N[NSum[(-1)^n(n^(1/n)-1),{n,1,Infinity},Method"AlternatingSigns",WorkingPrecision110],64];​​​​​​ST=NSum[(-1)^n(n^(1/n)-1),{n,1,Infinity},Method"AlternatingSigns",WorkingPrecision210];​​​​(*p=Table[n^(1/n),{n,2,64}];​​d=Table[Log[Prime[n]],{n,1,5}];​​e=Table[Exp[Prime[n]],{n,1,5}];​​s=Table[StieltjesGamma[n],{n,2,5}];*)​​r=Table[Pi^n,{n,2,67}];​​(*t=Table[Sum[x^(-n!),{n,2,Infinity}],{x,2,10}];*)​​dd=Union[(*t,p,1/p,d,1/d,s,1/s,e,1/e,...theseweretriedseperately*)r,1/r,{EulerGamma,GoldenRatio,GoldenAngle}];​​For[c=1,c<10,Block[{$MaxExtraPrecision=400},For[a=1,a<1000,result=TranscendentalRecognize[N[ST,110(*{28,64,100,110},"28"wasreplacedwitheachofthesesamplesizes*)],RandomSample[dd,5]];​​If[Abs[ST-Abs[result]]<10^-110,If[N[Abs[Denominator[result]],10]<10^4,Print["Simplest Expression: ",result];​​Print["Error: ",N[Abs[ST-Abs[result]],10]]]];a++]];c++]​​​​
Power
:Infinite expression
1
0
encountered.
Simplest Expression:
1
1052
16224950379073492638548
65
π
+
36980076885177876820985
64
π
+
43203855726258231471856
59
π
+
33480119179867469551733
58
π
+
15200019234302372801633
40
π
Error: 1.188310169×
-118
10
Power
:Infinite expression
1
0
encountered.
Simplest Expression:
1
1069
2407738790630506608574
65
π
+
2015737192125387195322
54
π
+
1374029826550259547760
52
π
+
3801113228818951221114
46
π
+
4915243062733563771080
39
π
Error: 4.169416914×
-115
10
Simplest Expression:
1
9219
12961345739997508271386
60
π
+
92664515819308204320560
49
π
-
50668856943432214267606
45
π
+
10702818493932297555001
42
π
+
132280493401832496822985
40
π
Error: 5.596849286×
-121
10
Simplest Expression:
1
1528
153496419640733578372215
65
π
+
19952671064595112265418
58
π
-
1519040746262392315381
57
π
-
236743424126773500718128
44
π
+
241884248163221298174462
42
π
Error: 4.528220703×
-123
10
Power
:Infinite expression
1
0
encountered.
General
:Further output of Power::infy will be suppressed during this calculation.
Simplest Expression:
1
34
-
816987238233752571822635601
67
π
+
1735404687960196266416183862
60
π
+
713674999906738904385570004
58
π
+
1423540456792124102683274409
53
π
Error: 1.356725427×
-111
10
Out[]=
$Aborted
...
In[]:=
​
2,000,000 optimal approximations of the 20 to 110 digits of MRB constant were made. By a vast margin, the 42 simplest found were of the following form, and were remarkably similar expressions equal to the MRB constant to more than 110 accurate digits.
​
Interestingly, all the inner denominators of these first-to-be found such rational-coefficient approximations to the MRB constant are of powers of
π
from
36
π
to
67
π
.
Theclosestonewasoundtwice:
Simplest Expression:
1
722
-
2816430872233976175430372
62
π
+
5957097815670284202075483
60
π
+
4424218174017480708311859
59
π
-
8072099516513147854361561
56
π
+
3192409539544820132530437
45
π
Error: 6.798165174×
-134
10
​
Simplest Expression:
1
722
-
2816430872233976175430372
62
π
+
5957097815670284202075483
60
π
+
4424218174017480708311859
59
π
-
8072099516513147854361561
56
π
+
3192409539544820132530437
45
π
Error: 6.798165174×
-134
10
"Simplest Expression: "
1
9829
11780815272846921339491439
66
π
-
9454446634820560766932241
59
π
-
6933452473184130184014486
58
π
-
9608226003969361773975237
57
π
+
13833668461810598004782066
44
π
Error: 9.787694535×
-133
10
Simplest Expression:
1
2131
-
10294084256347200003846148
65
π
+
6967133162807652571107565
64
π
+
347545356962160341271162
59
π
-
25177427607075559412461700
57
π
+
9422420158868391595375929
45
π
Error: 3.046571730×
-133
10
Simplest Expression:
1
199
-
9714089915919409138406
61
π
+
12213839844938905338610
59
π
-
23861825046536702985423
54
π
-
818762804867886579582
52
π
+
9032997220721828869718
41
π
Error: 5.390762258×
-115
10
Simplest Expression:
1
1969
574600728160998342739
58
π
+
977353715661272216646
57
π
-
2069322398693938769762
47
π
+
830702257795974686037
40
π
+
283540769574875165993
36
π
Error: 1.589711303×
-111
10
Simplest Expression:
1
2
-
274043676231736792233
67
π
+
10416401276131596360391
49
π
+
8331565086773668803864
48
π
-
2878373182826936594597
44
π
+
1774154322237604888022
43
π
Error: 2.578424152×
-112
10
Simplest Expression:
1
95
-
8778896325705027821831
65
π
-
4511368312215809760412
64
π
-
11224473801108068422388
58
π
+
30666853951092463428648
49
π
+
13537115381946876676097
42
π
Error: 1.394066556×
-114
10
Simplest Expression:
1
72
-
5022709862568054252146
62
π
+
6915467884897425469086
58
π
+
8436036169477165554041
50
π
-
278074297231976057835
44
π
+
3276901420809908649936
41
π
Error: 1.077422413×
-114
10
Simplest Expression:
1
760
3558484922814618996681
59
π
+
4517255303907734226981
53
π
+
360593113111658107712
52
π
+
1645449266612738417245
46
π
+
3494816246944647556926
39
π
Error: 3.935290151×
-113
10
Simplest Expression:
1
62
-
2463323831216348319806
66
π
+
13758274660583294926600
60
π
+
12108578488664280230316
59
π
-
1941155664326074081565
50
π
+
2814362319206579319356
41
π
Error: 9.872282059×
-115
10
Simplest Expression:
1
6161
2051524408851399572662
54
π
+
58336715524973494483
48
π
+
806585706547559366569
43
π
-
1743316223389646804045
42
π
+
915407153727919847762
36
π
Error: 4.954675558×
-113
10