Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Rodica Simion
open-in-new
<h2 id="biography">Biography</h2> <p>Simion was one of the top competitors in the Romanian national <a href="/facts/International_Mathematical_Olympiad/HWBMkwEq">mathematical olympiads</a>.<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a> She graduated from the <a href="/facts/University_of_Bucharest/tV846H8y">University of Bucharest</a> in 1974, and immigrated to the United States in 1976.<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a> She did her graduate studies at the <a href="/facts/University_of_Pennsylvania/LBBBULox">University of Pennsylvania</a>, earning a Ph.D. in 1981 under the supervision of <a href="/facts/Herbert_Wilf/SpfnF0dc">Herbert Wilf</a>.<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a><a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a> After teaching at <a href="/facts/Southern_Illinois_University/XPLs4wrJ">Southern Illinois University</a> and <a href="/facts/Bryn_Mawr_College/KwWWMNP7">Bryn Mawr College</a>, she moved to George Washington University in 1987, and became Columbian School Professor in 1997.<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a> </p> <h2 id="recognition">Recognition</h2> <p>She is included in a deck of playing cards featuring notable women mathematicians published by the <a href="/facts/Association_of_Women_in_Mathematics/XD8tfvun">Association of Women in Mathematics</a>.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> </p> <h2 id="research-contributions">Research contributions</h2> <p>Simion's thesis research concerned the <a href="/facts/Concave_function/HxVEBkce">concavity</a> and <a href="/facts/Unimodal_function/Xo3bhgeE">unimodality</a> of certain combinatorially defined sequences,<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a> and included what <a href="/facts/Richard_P._Stanley/8bQ4QrLM">Richard P. Stanley</a> calls "a very influential result" that the zeros of certain polynomials are all real.<a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a> </p><p>Next, with Frank Schmidt, she was one of the first to study the combinatorics of <a href="/facts/Permutation_pattern/ytUU2b91">sets of permutations defined by forbidden patterns</a>; she found a <a href="/facts/Bijective_proof/wQsz192E">bijective proof</a> that the <a href="/facts/Stack-sortable_permutation/xdLmgwmr">stack-sortable permutations</a> and the permutations formed by interleaving two monotonic sequences are equinumerous, and found <a href="/facts/Enumerations_of_specific_permutation_classes/T7H0wbtz">combinatorial enumerations of many permutation classes</a>.<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a><a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a> The "simsun permutations" were named after her and Sheila Sundaram, after their initial studies of these objects;<a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a><a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a> a simsun permutation is a permutation in which, for all <i>k</i>, the subsequence of the smallest <i>k</i> elements has no three consecutive elements in decreasing order.<a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a> </p><p>Simion also did extensive research on <a href="/facts/Noncrossing_partition/5foKcoEz">noncrossing partitions</a>, and became "perhaps the world's leading authority" on them.<a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a> </p> <h2 id="other-activities">Other activities</h2> <p>Simion was the main organizer of an exhibit about mathematics, <i>Beyond Numbers</i>, at the <a href="/facts/Maryland_Science_Center/pJp1LPP4">Maryland Science Center</a>, based in part on her earlier experience organizing a similar exhibit at George Washington University.<a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a><a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a> She was also a leader in George Washington University's annual Summer Program for Women in Mathematics.<a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a> As well as being a mathematician, Simion was a poet and painter;<a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a><a class="footnote-ref" id="fnref:19" href="#fn:19"><sup>19</sup></a> her poem "Immigrant Complex" was published in a collection of mathematical poetry in 1979.<a class="footnote-ref" id="fnref:20" href="#fn:20"><sup>20</sup></a> </p> <h2 id="selected-publications">Selected publications</h2> <ul><li>Simion, Rodica (1984), "A multi-indexed Sturm sequence of polynomials and unimodality of certain combinatorial sequences", <i><a href="/facts/Journal_of_Combinatorial_Theory/oYS6G76K">Journal of Combinatorial Theory</a></i>, Series A, 36 (1): 15–22, <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2F0097-3165%2884%2990075-X">10.1016/0097-3165(84)90075-X</a>, <a href="/facts/MR_(identifier)/uP137L11">MR</a> <a href="https://mathscinet.ams.org/mathscinet-getitem?mr=0728500">0728500</a>.</li> <li>Simion, Rodica; Schmidt, Frank W. (1985), "Restricted permutations", <i><a href="/facts/European_Journal_of_Combinatorics/a6jNXFuH">European Journal of Combinatorics</a></i>, 6 (4): 383–406, <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2Fs0195-6698%2885%2980052-4">10.1016/s0195-6698(85)80052-4</a>, <a href="/facts/MR_(identifier)/uP137L11">MR</a> <a href="https://mathscinet.ams.org/mathscinet-getitem?mr=0829358">0829358</a>.</li> <li>Simion, Rodica; Ullman, Daniel (1991), "On the structure of the lattice of noncrossing partitions", <i><a href="/facts/Discrete_Mathematics_(journal)/K4e6z8wQ">Discrete Mathematics</a></i>, 98 (3): 193–206, <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2F0012-365X%2891%2990376-D">10.1016/0012-365X(91)90376-D</a>, <a href="/facts/MR_(identifier)/uP137L11">MR</a> <a href="https://mathscinet.ams.org/mathscinet-getitem?mr=1144402">1144402</a>.</li> <li>Simion, Rodica (2000), "Noncrossing partitions", <i><a href="/facts/Discrete_Mathematics_(journal)/K4e6z8wQ">Discrete Mathematics</a></i>, 217 (1–3): 367–409, <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2FS0012-365X%2899%2900273-3">10.1016/S0012-365X(99)00273-3</a>, <a href="/facts/MR_(identifier)/uP137L11">MR</a> <a href="https://mathscinet.ams.org/mathscinet-getitem?mr=1766277">1766277</a>.</li></ul> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/Cyclohedron/MzJ6Nw9v">Cyclohedron</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Crapanzano, Theresa (January 20, 2000), "GW mourns after math professor passes away", The GW Hatchet. <a href="https://www.gwhatchet.com/2000/01/20/gw-mourns-after-math-professor-passes-away/" target="_blank">https://www.gwhatchet.com/2000/01/20/gw-mourns-after-math-professor-passes-away/</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Stanley, Richard P. (2000), "Rodica Simion: January 18, 1955 – January 7, 2000" (PDF), Pi Mu Epsilon Journal, 11: 83–86. <a href="/wiki/Richard_P._Stanley" target="_blank">/wiki/Richard_P._Stanley</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Stanley, Richard P. (2000), "Rodica Simion: January 18, 1955 – January 7, 2000" (PDF), Pi Mu Epsilon Journal, 11: 83–86. <a href="/wiki/Richard_P._Stanley" target="_blank">/wiki/Richard_P._Stanley</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Rodica Simion at the Mathematics Genealogy Project <a href="https://mathgenealogy.org/id.php?id=15214" target="_blank">https://mathgenealogy.org/id.php?id=15214</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Stanley, Richard P. (2000), "Rodica Simion: January 18, 1955 – January 7, 2000" (PDF), Pi Mu Epsilon Journal, 11: 83–86. <a href="/wiki/Richard_P._Stanley" target="_blank">/wiki/Richard_P._Stanley</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"Mathematicians of EvenQuads Deck 1", awm-math.org, retrieved 2022-06-18 <a href="https://awm-math.org/publications/playing-cards/deck1/#simion" target="_blank">https://awm-math.org/publications/playing-cards/deck1/#simion</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Wilf, Herbert (January 2000), Rodica Simion (1955–2000), Remarks at a special session of an AMS meeting in Washington, D.C.. <a href="/wiki/Herbert_Wilf" target="_blank">/wiki/Herbert_Wilf</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>Stanley, Richard P. (2000), "Rodica Simion: January 18, 1955 – January 7, 2000" (PDF), Pi Mu Epsilon Journal, 11: 83–86. <a href="/wiki/Richard_P._Stanley" target="_blank">/wiki/Richard_P._Stanley</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>Stanley, Richard P. (2000), "Rodica Simion: January 18, 1955 – January 7, 2000" (PDF), Pi Mu Epsilon Journal, 11: 83–86. <a href="/wiki/Richard_P._Stanley" target="_blank">/wiki/Richard_P._Stanley</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>Wilf, Herbert (January 2000), Rodica Simion (1955–2000), Remarks at a special session of an AMS meeting in Washington, D.C.. <a href="/wiki/Herbert_Wilf" target="_blank">/wiki/Herbert_Wilf</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p>Zeilberger, Doron (January 2000), RODICA SIMION (1955-2000): An (almost) Perfect Enumerator and Human Being. <a href="/wiki/Doron_Zeilberger" target="_blank">/wiki/Doron_Zeilberger</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>Sundaram, Sheila (2002), "Reminiscences of Rodica Simion", Advances in Applied Mathematics, 28 (3–4): 285–286, doi:10.1006/aama.2001.0785, MR 1899997. <a href="/wiki/Advances_in_Applied_Mathematics" target="_blank">/wiki/Advances_in_Applied_Mathematics</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p>Deutsch, Emeric; Elizalde, Sergi (2012), "Restricted simsun permutations", Annals of Combinatorics, 16 (2): 253–269, arXiv:0912.1361, doi:10.1007/s00026-012-0129-6, MR 2927606, S2CID 115172092. <a href="/wiki/Annals_of_Combinatorics" target="_blank">/wiki/Annals_of_Combinatorics</a> <a href="#fnref:13" class="footnote-back-ref">↩</a></p></li> <li id="fn:14"><p>Stanley, Richard P. (2000), "Rodica Simion: January 18, 1955 – January 7, 2000" (PDF), Pi Mu Epsilon Journal, 11: 83–86. <a href="/wiki/Richard_P._Stanley" target="_blank">/wiki/Richard_P._Stanley</a> <a href="#fnref:14" class="footnote-back-ref">↩</a></p></li> <li id="fn:15"><p>Stanley, Richard P. (2000), "Rodica Simion: January 18, 1955 – January 7, 2000" (PDF), Pi Mu Epsilon Journal, 11: 83–86. <a href="/wiki/Richard_P._Stanley" target="_blank">/wiki/Richard_P._Stanley</a> <a href="#fnref:15" class="footnote-back-ref">↩</a></p></li> <li id="fn:16"><p>Bonin, Joseph E. (2002), "A remembrance of Rodica Simion", Advances in Applied Mathematics, 28 (3–4): 280–281, doi:10.1006/aama.2001.0783, MR 1899995. <a href="/wiki/Advances_in_Applied_Mathematics" target="_blank">/wiki/Advances_in_Applied_Mathematics</a> <a href="#fnref:16" class="footnote-back-ref">↩</a></p></li> <li id="fn:17"><p>Stanley, Richard P. (2000), "Rodica Simion: January 18, 1955 – January 7, 2000" (PDF), Pi Mu Epsilon Journal, 11: 83–86. <a href="/wiki/Richard_P._Stanley" target="_blank">/wiki/Richard_P._Stanley</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></p></li> <li id="fn:18"><p>Zeilberger, Doron (January 2000), RODICA SIMION (1955-2000): An (almost) Perfect Enumerator and Human Being. <a href="/wiki/Doron_Zeilberger" target="_blank">/wiki/Doron_Zeilberger</a> <a href="#fnref:18" class="footnote-back-ref">↩</a></p></li> <li id="fn:19"><p>Kalai, Gil (January 7, 2000), Rodica Simion: Immigrant Complex, Combinatorics and more. <a href="/wiki/Gil_Kalai" target="_blank">/wiki/Gil_Kalai</a> <a href="#fnref:19" class="footnote-back-ref">↩</a></p></li> <li id="fn:20"><p>Robson, Ernest M.; Wimp, Jet, eds. (1979), Against infinity: an anthology of contemporary mathematical poetry, Primary Press, pp. 65–66, ISBN 9780934982016. <a href="9780934982016" target="_blank">9780934982016</a> <a href="#fnref:20" class="footnote-back-ref">↩</a></p></li> </ol>