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A261861 Number of compositions of n into distinct parts where each part i is marked with a word of length i over a denary alphabet whose letters appear in alphabetical order and all letters occur at least once in the composition. 2
333051, 4822430, 79871395, 832560780, 9644631215, 503145835150, 1977105518235, 13353202808060, 72444344358890, 431802346970780, 2638310862477610, 102808411342614000, 286995037461236030, 1470656290936993540, 5931973064021096010, 27203387338778029760 (list; graph; refs; listen; history; text; internal format)
OFFSET
10,1
COMMENTS
Also number of matrices with ten rows of nonnegative integer entries and without zero rows or columns such that the sum of all entries is equal to n and the column sums are distinct.
LINKS
FORMULA
a(n) = A261836(n,10).
MAPLE
b:= proc(n, i, p, k) option remember;
`if`(i*(i+1)/2<n, 0, `if`(n=0, p!, b(n, i-1, p, k)+
`if`(i>n, 0, b(n-i, i-1, p+1, k)*binomial(i+k-1, k-1))))
end:
a:= n->(k->add(b(n$2, 0, k-i)*(-1)^i*binomial(k, i), i=0..k))(10):
seq(a(n), n=10..30);
CROSSREFS
Column k=10 of A261836.
Sequence in context: A069337 A187138 A185843 * A234129 A232412 A346028
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Sep 03 2015
STATUS
approved

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Last modified February 24 01:05 EST 2024. Contains 370288 sequences. (Running on oeis4.)