A261843 Number of compositions of n into distinct parts where each part i is marked with a word of length i over a quinary alphabet whose letters appear in alphabetical order.

1, 5, 15, 185, 420, 1876, 19320, 42610, 149115, 495205, 5516001, 10570145, 35897010, 97383790, 320607680, 3412039628, 6292069835, 19106603405, 49239854095, 138462457915, 378598491878, 4312038483490, 7316190877970, 21527078513430, 50933081112485

Offset

0,2

Comments

Also matrices with five rows of nonnegative integers with distinct positive column sums and total element sum n.

Links

Alois P. Heinz, Table of n, a(n) for n = 0..5000

Maple

b:= proc(n, i, p) option remember;
      `if`(i*(i+1)/2<n, 0, `if`(n=0, p!, b(n, i-1, p)+
      `if`(i>n, 0, b(n-i, i-1, p+1)*binomial(i+4, 4))))
    end:
a:= n-> b(n$2, 0):
seq(a(n), n=0..30);

Crossrefs

Column k=5 of A261835.

Sequence in context: A034980 A174850 A143048 * A120602 A004130 A088869

Adjacent sequences: A261840 A261841 A261842 * A261844 A261845 A261846

Keyword

nonn

Author

Alois P. Heinz, Sep 03 2015

Status

approved