@Test
public void testSeqIndexesByRatios() throws Exception {

    ConcatSequencer<String> concat = new ConcatSequencer<>();
    int[] ints = concat.seqIndexesByRatios(strings(a,b), ratios(2, 5));
    assertThat(ints).containsExactly(0,0,1,1,1,1,1);
}