Winning Numbers Weekly Range

let
  Source = Excel.CurrentWorkbook(){[Name = "Input"]}[Content], 
  S = Table.AddColumn(
    Source, 
    "Max Occurred No", 
    each 
      let
        g = each [Group], 
        w = each [Week No], 
        n = Number.Mod(w(_), 100), 
        c = Number.From(n < 8), 
        b = (Number.IntegerDivide(w(_), 100) - c) * 100 + c * 52 + n - 7, 
        r = Table.SelectRows(Source, (r) => (g(r) = g(_)) and w(r) <= w(_) and w(r) >= b), 
        t = Table.SelectRows(Source, (r) => (g(r) = g(_)) and w(r) <= b)
      in
        if Table.RowCount(r) > 1 and Table.RowCount(t) > 0 then
          Text.Combine(List.Transform(List.Sort(List.Modes(r[Winning No])), Text.From), ", ")
        else
          null
  )
in
  S

let
 Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
 Years = List.Distinct(List.Transform(Source[Week No], each Text.Start(Text.From(_),4))),
 YearsWeek = List.TransformMany(Years, (x)=> {1..52}, (x,y)=> x&Text.PadStart(Text.From(y),2,"0")),
 Group = Table.Group(Source, {"Group"}, {{"A", each 
let
a = Table.ToRows(Table.RemoveColumns(_, "Group")),
b = YearsWeek,
c = List.Distinct(List.TransformMany(b, (x)=> {0..List.Count(a)-1}, (x,y)=> if Number.From(x)=a{y}{0} then {x,a{y}{1}} else {x,null}) ),
d = List.Sort(c, {each _{0}, 1}),
e = Table.RemoveFirstN(Table.FromRows(d, List.Skip(Table.ColumnNames(_))), each [Winning No] = null),
f = Table.ReverseRows(Table.RemoveFirstN(Table.ReverseRows(Table.TransformColumns(Table.Group(e, "Week No", {"Winning No", each List.Select([Winning No], each _ <> null)}), {"Winning No", each try _{0} otherwise null})), each [Winning No] = null)), 
                    
                  
          

let 
i = List.FirstN(List.Skip(f[Winning No], [Idx]), 8),
j = List.Select(List.Transform(List.Distinct(i), (x)=> {x, List.Count(List.Select(i, each x = _))}), each _{0}<>null),
k = List.Max(List.Transform({0..List.Count(j)-1}, each j{_}{1})),
l = List.Sort(List.Transform(List.Select(j, each _{1}=k), each Text.From(_{0})))
in Text.Combine(l, ", "))
in Table.RemoveColumns(h, "Idx")}}),
 Sol = Table.SelectRows(Table.ExpandTableColumn(Group, "A", Table.ColumnNames(Group[A]{0})), each [Winning No]<>null)
in
 Sol
                    
                  
          

let
 fxYWAddWeeks = (yw, n)=>let 
 y = Number.IntegerDivide(yw,100), w=Number.Mod(yw,100),
 d = Date.AddWeeks(hashtag#date(y,1,1), w+n)
 in Date.Year(d)*100 + Date.WeekOfYear(d),
 
 Source = Excel.CurrentWorkbook(){[Name="tData161"]}[Content],
 Group = Table.Group(Source, "Group", {"All", each let
 _tb = Table.Buffer(_), 
 _WMin = fxYWAddWeeks (List.Min([Week No]), 6), 
 AddOcc = Table.AddColumn(_, "Max Occured No", each let
 _W = [Week No], _lW = {fxYWAddWeeks(_W, -8).._W}, 
 _t = Table.SelectRows(_tb, 
 each (_W>=_WMin and List.Contains(_lW, [Week No]))),
 _l1 = List.Modes(_t[Winning No]),
 _l2 = List.Transform(List.Sort(List.Distinct(_l1)), Number.ToText) 
 in Text.Combine(_l2, ", ") )
 in AddOcc}),
 Expand = Table.ExpandTableColumn(Group, "All", {"Week No", "Winning No", "Max Occured No"})
in 
 Expand


                    
                  
          

let
  Source = Excel.CurrentWorkbook(){[Name = "Table1"]}[Content], 
  dup = Table.DuplicateColumn(Source, "Week No", "Week"), 
  yr = Table.AddColumn(dup, "Year", each Text.Start(Text.From([Week No], "en-GB"), 4), type text), 
  ct = Table.TransformColumnTypes(
    yr, 
    {
      {"Group", type text}, 
      {"Week No", type text}, 
      {"Winning No", Int64.Type}, 
      {"Week", Int64.Type}, 
      {"Year", Int64.Type}
    }
  ), 
  wk = Table.TransformColumns(
    ct, 
    {
      {
        "Week", 
        each 
          let
            t = Text.From(_)
          in
            (Int64.From(Text.Start(t, 4)) * 52) + Int64.From(Text.End(t, 2)), 
        Int64.Type
      }
    }
  ), 
  ans = Table.AddColumn(
    wk, 
    "r", 
    each 
      let
        pt = Table.SelectRows(wk, (x) => (x[Group] = [Group])), 
        mw = List.Min(pt[Week]), 
        w = [Week], 
        w7 = w - 7, 
        t = 
          if w7 >= mw then
            let
              l = Table.SelectRows(pt, (x) => (x[Week] <= w) and (x[Week] >= w7))[Winning No], 
              g = Table.FromRows(
                List.Transform(l, (x) => {x, List.Count(List.PositionOf(l, x, Occurrence.All))}), 
                {"num", "count"}
              ), 
              mg = List.Max(g[count]), 
              sg = Table.SelectRows(g, (x) => x[count] = mg), 
              r = Text.Combine(
                List.Transform(List.Sort(List.Distinct(sg[num])), (x) => Text.From(x)), 
                ", "
              )
            in
              r
          else
            null
      in
        t, 
    type text
  )
in
  ans

=LET(g,A2:A30,w,B2:B30,v,LEFT(w,4)*52+RIGHT(w,2),MAP(g,v,LAMBDA(a,b,REPT(TEXTJOIN(", ",,SORT(MODE.MULT(IF({1,1},FILTER(C2:C30,(g=a)*(v<=b)*(v>b-8)))))),b-6>MIN(IF(g=a,v))))))

=LET(g,A2:A30,w,B2:B30,MAP(g,w,LAMBDA(a,b,
LET(j,b+SEQUENCE(8)-8,e,--RIGHT(j,2),
v,LEFT(j,4),i,IFS(e=0,v-1&52,e>52,v&e-48,1,j),
u,SORT(TOCOL(XLOOKUP(a&i,g&w,C2:C30),2)),
IF(MIN(i)>=MINIFS(w,g,a),
ARRAYTOTEXT(MODE.MULT(VSTACK(u,u))),"")))))

https://www.linkedin.com/posts/owenhprice_apply-a-custom-function-to-grouped-data-activity-7170870641196253185-5z_K