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A108890
a(n) = floor(Product_{k=1..n} (Sum_{j=1..k} 1/j)).
1
1, 1, 2, 5, 13, 32, 83, 225, 638, 1871, 5651, 17537, 55772, 181348, 601754, 2034368, 6997316, 24456376, 86764857, 312157366, 1137925574, 4199870789, 15683541837, 59220398058, 225982562259, 871031643495, 3389581971377, 13311468152196
OFFSET
1,3
LINKS
MAPLE
S:= ListTools:-PartialSums([seq(1/j, j=1..100)]):
P:= 1: R:= 1;
for k from 2 to 100 do
P:= P * S[k];
R:= R, floor(P);
od:
R; # Robert Israel, Nov 23 2022
MATHEMATICA
f[n_] := Floor[ Product[ Sum[1/j, {j, k}], {k, n}]]; Table[ f[n], {n, 28}] (* Robert G. Wilson v, Jul 18 2005 *)
PROG
(PARI) for(n=1, 50, print1(floor(prod(k=1, n, sum(j=1, k, 1/j))), ", ")) \\ Lambert Klasen, Jul 18 2005
CROSSREFS
Sequence in context: A298535 A110320 A219230 * A220739 A337282 A366117
KEYWORD
easy,nonn
AUTHOR
Leroy Quet, Jul 14 2005
EXTENSIONS
More terms from Lambert Klasen (lambert.klasen(AT)gmx.net), Hauke Worpel (hw1(AT)email.com), Ryan Propper and Robert G. Wilson v, Jul 18 2005
STATUS
approved