Generate an Alphabetic Sequence


http://blog.jooq.org/2015/09/09/how-to-use-java-8-functional-programming-to-generate-an-alphabetic-sequence/
’m looking for a way of generating an alphabetic sequence:
A, B, C, ..., Z, AA, AB, AC, ..., ZZ.
private static String getString(int n) {
    char[] buf = new char[(int) floor(log(25 * (n + 1)) / log(26))];
    for (int i = buf.length - 1; i >= 0; i--) {
        n--;
        buf[i] = (char) ('A' + n % 26);
        n /= 26;
    }
    return new String(buf);
}

JDK8
    public static void main(String[] args) {
        int max = 3;
 
        List<String> alphabet = Seq
            .rangeClosed('A', 'Z')
            .map(Object::toString)
            .toList();
 
        Seq.rangeClosed(1, max)
           .flatMap(length ->
               Seq.rangeClosed(1, length - 1)
                  .foldLeft(Seq.seq(alphabet), (s, i) ->
                      s.crossJoin(Seq.seq(alphabet))
                       .map(t -> t.v1 + t.v2)))
           .forEach(System.out::println);
    }


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