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 A232967 Irregular triangle read by rows: row n lists the rank sizes of the "electrical" poset EP_n of circular planar graphs with n boundary vertices. 1
 1, 1, 1, 1, 3, 3, 1, 1, 6, 14, 16, 10, 4, 1, 1, 10, 40, 85, 110, 97, 65, 35, 15, 5, 1, 1, 15, 90, 295, 609, 873, 948, 840, 636, 421, 246, 126, 56, 21, 6, 1, 1, 21, 175, 805, 2366, 4872, 7567, 9459, 10031, 9359, 7861, 6027, 4249, 2765, 1661, 917, 462, 210, 84, 28, 7, 1, 1, 28, 308, 1876, 7350, 20272, 42090, 69620, 96334, 115980, 125044, 123176, 112380, 95836, 76868, 58220, 41734, 28344, 18236, 11096, 6364, 3424, 1716, 792, 330, 120, 36, 8, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS More than the usual number of terms are given, since the connection with A111088 seems rather mysterious. REFERENCES J. Alman, C. Lian, B. Tran, Circular Planar Electrical Networks: Posets and Positivity, 2013; http://www.math.umn.edu/~reiner/REU/AlmanLianTran2013.pdf LINKS EXAMPLE Triangle begins: 1, 1, 1, 1, 3, 3, 1, 1, 6, 14, 16, 10, 4, 1, 1, 10, 40, 85, 110, 97, 65, 35, 15, 5, 1,, 1, 15, 90, 295, 609, 873, 948, 840, 636, 421, 246, 126, 56, 21, 6, 1, 1, 21, 175, 805, 2366, 4872, 7567, 9459, 10031, 9359, 7861, 6027, 4249, 2765, 1661, 917, 462, 210, 84, 28, 7, 1, 1, 28, 308, 1876, 7350, 20272, 42090, 69620, 96334, 115980, 125044, 123176, 112380, 95836, 76868, 58220, 41734, 28344, 18236, 11096, 6364, 3424, 1716, 792, 330, 120, 36, 8, 1, ... CROSSREFS Row sums give A111088. Sequence in context: A244500 A300695 A296186 * A144163 A080858 A144228 Adjacent sequences:  A232964 A232965 A232966 * A232968 A232969 A232970 KEYWORD nonn,tabf AUTHOR N. J. A. Sloane, Dec 04 2013 STATUS approved

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Last modified October 15 01:40 EDT 2019. Contains 328025 sequences. (Running on oeis4.)