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A377401
a(n) = denominator((1/n!)*Sum_{k=1..n} 1/(2*k)).
1
1, 2, 8, 72, 576, 14400, 28800, 470400, 22579200, 1828915200, 18289152000, 2212987392000, 26555848704000, 4487938430976000, 62831138033664000, 942467070504960000, 30158946256158720000, 8715935468029870080000, 52295612808179220480000, 18878716223752698593280000
OFFSET
0,2
FORMULA
Conjecture: numerator((1/n!)*Sum_{k=1..n} 1/(2*k)) = A060746(n).
MATHEMATICA
a[n_]:=Denominator[Sum[1/(2*k), {k, n}]/n!]; Array[a, 20, 0]
PROG
(PARI) a(n) = denominator(sum(k=1, n, 1/(2*k))/n!); \\ Michel Marcus, Oct 29 2024
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Stefano Spezia, Oct 27 2024
STATUS
approved