dalex

const
    maxn = 100000;

var
    ans, n: int64;
    i, j, k, maxi, t: longint;
    a: array[1..100] of longint;
    b: array[1..100, 1..maxn] of int64;

function get_answer(i: longint; n: int64): int64;
var ans: int64;
begin
    if n = 0 then begin
        get_answer := 0;
        exit;
    end;
    if i > k then begin
        get_answer := n;
        exit;
    end;
    if (n <= maxn) and (b[i, n] <> -1) then begin
        get_answer := b[i, n];
        exit;
    end;
    ans := get_answer(i + 1, n) - get_answer(i + 1, n div a[i]);
    if (n <= maxn) then b[i, n] := ans;
    get_answer := ans;
end;

begin
    read(n, k);
    for i := 1 to k do read(a[i]);

    // sort in descending order
    for j := 1 to k - 1 do begin
        maxi := j;
        for i := j + 1 to k do begin
            if a[i] > a[maxi] then maxi := i;
        end;
        t := a[j]; a[j] := a[maxi]; a[maxi] := t;
    end;

    for i := 1 to k do
        for j := 1 to maxn do
            b[i, j] := -1;

    writeln(get_answer(1, n));
end.