A244102 Number of ballot sequences of length n having 5 largest parts.
1, 0, 0, 0, 0, 42, 132, 297, 572, 1001, 7644, 38584, 227460, 880668, 3560106, 13136733, 53948258, 260567615, 1322074776, 7132302760, 36927209090, 189472194730, 965322122310, 4935547435455, 26391699530094, 143808787394511, 824237501959916, 4756694235326336
Offset: 5
Keywords
Links
- Alois P. Heinz, Table of n, a(n) for n = 5..100
Crossrefs
Column k=5 of A238123.
Programs
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Mathematica
b[n_, l_List] := b[n, l] = If[n < 1, x^l[[-1]], b[n - 1, Append[l, 1]] + Sum[If[i == 1 || l[[i - 1]] > l[[i]], b[n - 1, ReplacePart[l, i -> l[[i]] + 1]], 0], {i, 1, Length[l]}]]; a[n_] := Coefficient[b[n - 1, {1}], x, 5]; Table[a[n], {n, 5, 30}] (* Jean-François Alcover, Feb 10 2015, after A238123 *)
Comments