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A069120 Integers of the form k!*sum(i=1..k, 1/(i*2^i) ). 2

%I

%S 4,3489,906408439650,17919252390718041882750,

%T 5699637429226533498825333877162500,

%U 179263970680739996376691111034230475370480684738369155859375

%N Integers of the form k!*sum(i=1..k, 1/(i*2^i) ).

%H Robert Israel, <a href="/A069120/b069120.txt">Table of n, a(n) for n = 1..10</a>

%e 4 is in the sequence because for k = 3, 3!*(1/1/2^1 + 1/2/2^2 + 1/3/2^3) = 4 is an integer. - _Robert Israel_, May 18 2014

%p select(type,[seq](k!*add(1/i/2^i,i=1..k),k=1..100),integer); # _Robert Israel_, May 18 2014

%Y Cf. A069119.

%K easy,nonn

%O 1,1

%A _Benoit Cloitre_, Apr 07 2002

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Last modified October 20 18:00 EDT 2021. Contains 348111 sequences. (Running on oeis4.)