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 A320979 Number of permutations p of [n] such that the up-down signature of p has nonnegative partial sums with a maximal value of five. 2
 0, 1, 6, 254, 1835, 47673, 416221, 9565156, 99383961, 2250472801, 27333591309, 635688426842, 8878319017022, 215812184750821, 3416973303551969, 87455366666951644, 1550782738938548075, 41903722165381482287, 823596208419940694670, 23503436481574417378942 (list; graph; refs; listen; history; text; internal format)
 OFFSET 5,3 LINKS Alois P. Heinz, Table of n, a(n) for n = 5..453 FORMULA a(n) = A262130(n) - A262129(n). MAPLE b:= proc(u, o, c) option remember; `if`(c<0 or c>5, 0, `if`(u+o=0,        x^c, (p-> add(coeff(p, x, i)*x^max(i, c), i=0..5))(add(        b(u-j, o-1+j, c-1), j=1..u)+add(b(u+j-1, o-j, c+1), j=1..o))))     end: a:= n-> coeff(add(b(j-1, n-j, 0), j=1..n), x, 5): seq(a(n), n=5..30); CROSSREFS Column k=5 of A262125. Cf. A262129, A262130. Sequence in context: A332563 A041853 A168476 * A279869 A271501 A113900 Adjacent sequences:  A320976 A320977 A320978 * A320980 A320981 A320982 KEYWORD nonn AUTHOR Alois P. Heinz, Oct 25 2018 STATUS approved

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Last modified February 29 09:29 EST 2020. Contains 332355 sequences. (Running on oeis4.)