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 A333504 Sum of the heights of all lattice paths from (0,0) to (n,0) that do not go below the x-axis, and at (x,y) only allow steps (1,v) with v in {-1,0,1,...,y+1}. 6
 0, 0, 1, 3, 9, 28, 88, 282, 921, 3058, 10302, 35159, 121406, 423704, 1493046, 5307276, 19014642, 68609686, 249149529, 910000728, 3341113126, 12325295866, 45664033813, 169846998495, 634020229888, 2374550269819, 8920273989351, 33604033638696, 126919824985533 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS Alois P. Heinz, Table of n, a(n) for n = 0..400 Wikipedia, Counting lattice paths MAPLE b:= proc(x, y, h) option remember; `if`(x=0, h, add((t->      `if`(x>t, b(x-1, t, max(h, t)), 0))(y-j), j=-1-y..min(1, y)))     end: a:= n-> b(n, 0\$2): seq(a(n), n=0..33); MATHEMATICA b[x_, y_, h_] := b[x, y, h] = If[x == 0, h, Sum[With[{t = y - j},      If[x > t, b[x - 1, t, Max[h, t]], 0]], {j, -1 - y, Min[1, y]}]]; a[n_] := b[n, 0, 0]; a /@ Range[0, 33] (* Jean-François Alcover, Apr 26 2021, after Alois P. Heinz *) CROSSREFS Cf. A333069, A333070, A333071, A333498, A333608. Sequence in context: A022020 A195675 A170953 * A199104 A049220 A094790 Adjacent sequences:  A333501 A333502 A333503 * A333505 A333506 A333507 KEYWORD nonn AUTHOR Alois P. Heinz, Mar 24 2020 STATUS approved

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Last modified July 25 14:49 EDT 2021. Contains 346290 sequences. (Running on oeis4.)