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A344144
Decimal expansion of Sum_{n>=0} A000108(n)/n!.
0
5, 0, 9, 0, 6, 7, 8, 7, 2, 9, 3, 1, 7, 1, 6, 5, 6, 2, 2, 9, 7, 8, 6, 7, 7, 7, 1, 9, 9, 0, 7, 4, 9, 8, 4, 3, 7, 9, 7, 3, 8, 5, 1, 6, 8, 0, 2, 0, 9, 3, 7, 5, 6, 1, 6, 5, 2, 5, 1, 2, 7, 2, 4, 3, 1, 1, 0, 6, 5, 3, 6, 0, 2, 5, 8, 4, 9, 1, 7, 7, 9, 7, 4, 3, 9, 3, 5
OFFSET
1,1
FORMULA
Equals e^2 * BesselI(2,2) = A072334 * A229020. - Amiram Eldar, May 17 2021
EXAMPLE
5.09067872931716562297867771990749843797385168020937561652512724311065360258491...
MATHEMATICA
RealDigits[E^2 * BesselI[2, 2], 10, 100][[1]] (* Amiram Eldar, May 17 2021 *)
PROG
(PARI) suminf(n=0, (2*n)!/(n!*n!*(n+1)!)) \\ Michel Marcus, May 16 2021
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Ya-Ping Lu, May 10 2021
STATUS
approved