segment_vector_sequence is in the heirarchy of segment creation, for which you will also need:
segment_vectors_*
segment_vector_sequence(segment_elements, firstStepMatch = FALSE)dynamicSegment,
orFiltersForSegment,
segmentDefinition,
segmentDimensionFilter,
segmentFilterClause,
segmentFilter,
segmentMetricFilter,
segmentObj_ga4,
segmentSequenceStep,
segment_define,
segment_element,
segment_vector_simple,
sequenceSegment,
simpleSegment