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A261844 Number of compositions of n into distinct parts where each part i is marked with a word of length i over a senary alphabet whose letters appear in alphabetical order. 2
1, 6, 21, 308, 798, 4116, 51114, 126288, 502947, 1912318, 26074881, 55301652, 210871038, 643901916, 2416831656, 32128430000, 64611765009, 218800524222, 625968110257, 1971079800312, 6127902153366, 88805517515284, 163129580373222, 530136843388056 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
Also matrices with six rows of nonnegative integers with distinct positive column sums and total element sum n.
LINKS
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+5, 5))))
end:
a:= n-> b(n$2, 0):
seq(a(n), n=0..30);
CROSSREFS
Column k=6 of A261835.
Sequence in context: A213680 A164643 A190275 * A007594 A316775 A181593
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Sep 03 2015
STATUS
approved

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Last modified February 29 23:21 EST 2024. Contains 370428 sequences. (Running on oeis4.)