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A323340 Denominator of the sum of inverse products of parts in all compositions of n. 9
1, 1, 2, 3, 3, 60, 360, 70, 1680, 3780, 75600, 138600, 285120, 129729600, 363242880, 3405402000, 1009008000, 308756448000, 5557616064000, 52797352608000, 351982350720000, 221748880953600, 1524523556556000, 738190353700800, 13464592051502592000 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
Denominators of the INVERT transform of reciprocal integers.
LINKS
FORMULA
a(n) = denominator( A007840(n)/n! ).
MAPLE
b:= proc(n) option remember;
`if`(n=0, 1, add(b(n-j)/j, j=1..n))
end:
a:= n-> denom(b(n)):
seq(a(n), n=0..25);
MATHEMATICA
nmax = 20; Denominator[CoefficientList[Series[1/(1 + Log[1-x]), {x, 0, nmax}], x]] (* Vaclav Kotesovec, Feb 12 2024 *)
CROSSREFS
See A323339 for more information.
Sequence in context: A242786 A214219 A365223 * A280895 A088266 A116889
KEYWORD
nonn,frac
AUTHOR
Alois P. Heinz, Jan 11 2019
STATUS
approved

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Last modified May 26 07:52 EDT 2024. Contains 372807 sequences. (Running on oeis4.)