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 A124921 Distributes the number of permutations in the alternating group; cf. A060351 1
 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 3, 1, 1, 3, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,11 COMMENTS The symmetric group distribution of permutation descents is summarized in Table A008292; for example 1 57 302 302 57 1 sums the following A060351 values: 1.......5.......10.......10.......5.......1 .......14.......35.......35.......14....... .......19.......26.......40.......19....... .......14.......40.......19.......14....... ........5.......61.......26.......5....... ................26.......61.............. ................19.......40.............. ................40.......26.............. ................35.......35.............. ................10.......10.............. LINKS EXAMPLE The distribution is based on the frequency of descents; for example, when permuting four symbols the 12 patterns are ddd ddu dud udu dud duu udd udu dud udu uud and uuu yielding the frequency distribution 1 1 3 1 1 3 1 1 1; 1; 1, 0; 1, 1, 1, 0; 1, 1, 3, 1, 1, 3, 1, 1; CROSSREFS Cf. A001710 (row sums), A008292, A060351, A011782 (row lengths). Sequence in context: A218332 A322506 A103496 * A267863 A262681 A076498 Adjacent sequences:  A124918 A124919 A124920 * A124922 A124923 A124924 KEYWORD more,tabf,nonn,uned AUTHOR Alford Arnold, Nov 16 2006 STATUS approved

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Last modified June 19 13:11 EDT 2019. Contains 324222 sequences. (Running on oeis4.)