A241696 Number of Carlitz compositions of n with exactly six descents.

13, 81, 336, 1151, 3437, 9286, 23271, 54846, 122857, 263680, 545412, 1092394, 2126688, 4036767, 7490050, 13614573, 24287970, 42592752, 73525406, 125089010, 209962350, 348026885, 570159824, 923885796, 1481735623, 2353522164, 3704254256, 5780115565, 8945915366

Offset

18,1

Comments

No two adjacent parts of a Carlitz composition are equal.

Links

Alois P. Heinz, Table of n, a(n) for n = 18..1000

Maple

b:= proc(n, i) option remember; `if`(n=0, 1,
       convert(series(add(`if`(i=j, 0, b(n-j, j)*
      `if`(j<i, x, 1)), j=1..n), x, 7), polynom))
    end:
a:= n-> coeff(b(n, 0), x, 6):
seq(a(n), n=18..50);

Crossrefs

Column k=6 of A241701.

Sequence in context: A297678 A189451 A133718 * A052255 A362545 A082203

Adjacent sequences: A241693 A241694 A241695 * A241697 A241698 A241699

Keyword

nonn

Author

Alois P. Heinz, Apr 27 2014

Status

approved