A244165 Number of compositions of n in which the minimal multiplicity of parts equals 2.

1, 0, 1, 0, 7, 10, 32, 31, 71, 77, 222, 342, 971, 1936, 4681, 9662, 19440, 38304, 76458, 143542, 281447, 536472, 1051100, 2039870, 4055916, 8030958, 16168611, 32510383, 65705473, 132895297, 269206168, 544002516, 1099360989, 2217243856, 4464684513, 8975720721

Offset

2,5

Links

Alois P. Heinz, Table of n, a(n) for n = 2..400

Maple

b:= proc(n, i, p, k) option remember; `if`(n=0, p!, `if`(i<1, 0,
      add(b(n-i*j, i-1, p+j, k)/j!, j=[0, $max(1, k)..n/i])))
    end:
a:= n-> b(n$2, 0, 2) -b(n$2, 0, 3):
seq(a(n), n=2..50);

Crossrefs

Column k=2 of A242451.

Sequence in context: A102574 A317797 A284418 * A119169 A095756 A241251

Adjacent sequences: A244162 A244163 A244164 * A244166 A244167 A244168

Keyword

nonn

Author

Alois P. Heinz, Jun 21 2014

Status

approved