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Numerators of n-th approximation of factorial (also called harmonic) expansion of Pi.
2

%I #11 Aug 30 2019 04:00:39

%S 3,3,3,25,47,2261,15833,42223,42223,11400211,1672031,136802537,

%T 2173640311,2173640311,342348348983,5975534818613,372475003693547,

%U 21511925347007,76431870757915873,56199904969055789,4223866541884824563

%N Numerators of n-th approximation of factorial (also called harmonic) expansion of Pi.

%C Denominators are given in A131446. Rationals in lowest terms.

%H W. Lang, <a href="/A131445/a131445.txt">Rationals and values</a>.

%F a(n) = numerator(r(n)), with r(n) = Sum_{k=1..n} b(k)/k! with b(k) = A075874(k) (factorial expansion of Pi).

%e Rationals r(n): 3, 3, 3, 25/8, 47/15, 2261/720, 15833/5040, 42223/13440, 42223/13440, ...

%K nonn,frac,easy

%O 1,1

%A _Wolfdieter Lang_, Aug 07 2007