%I #23 Jun 04 2023 01:42:33

%S 9,9,1,6,6,6,9,4,2,2,3,9,0,9,4,1,9,0,5,6,3,4,2,2,9,0,8,4,5,3,9,8,6,2,

%T 0,5,3,1,7,5,9,1,5,2,5,0,6,7,8,0,8,3,9,3,3,5,8,1,3,5,9,3,9,3,7,7,8,5,

%U 4,7,5,0,2,8,2,5,5,9,2,0,8,1,8,6,3,8,9

%N Decimal expansion of the constant Sum_{k>=0} (-1)^k/(5*k)!.

%H Michael I. Shamos, <a href="http://euro.ecom.cmu.edu/people/faculty/mshamos/cat.pdf">A catalog of the real numbers</a> (2011).

%e 0.9916669422390941905634229...

%t RealDigits[HypergeometricPFQ[{}, {1/5, 2/5, 3/5, 4/5}, -1/5^5], 10, 120][[1]] (* _Amiram Eldar_, Jun 04 2023 *)

%o (PARI) sumalt(k=0, (-1)^k/(5*k)!) \\ _Michel Marcus_, Jul 18 2021

%Y Cf. A068985, A049470, A346441, A346440, A346438, A346437, A346436, A346435, A196498.

%K nonn,cons

%O 0,1

%A _Sean A. Irvine_, Jul 17 2021