ner_tags: O O O O O O B-Person I-Person I-Person O B-Model I-Model I-Model O O O O O B-Model I-Model O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B-Software I-Software O O O O O O B-Organization I-Organization I-Organization I-Organization O B-Grant O B-Grant O O O O O O O O O O O O O O O O
tokens: Acknowledgements We would like to thank Douglas C. Heggie for N -body simulations (referred in the text as DH simulations) and for very valuable discussions concerning blue straggler spatial distributions in star clusters. Results from these simulations added much confidence to the validity of the results obtained with the mocca code. The project was supported partially by Polish National Science Center grants DEC-2011/01/N/ST9/06000 and DEC-2012/07/B/ST9/04412. We thank anonymous referee for great comments and suggestions. It helped us to improve the paper.