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A347910
Decimal expansion of Integral_{x=0..1} exp(x^2) dx.
2
1, 4, 6, 2, 6, 5, 1, 7, 4, 5, 9, 0, 7, 1, 8, 1, 6, 0, 8, 8, 0, 4, 0, 4, 8, 5, 8, 6, 8, 5, 6, 9, 8, 8, 1, 5, 5, 1, 2, 0, 8, 7, 0, 0, 9, 6, 2, 1, 6, 7, 3, 9, 1, 8, 5, 6, 6, 0, 1, 1, 4, 5, 8, 0, 2, 1, 8, 7, 6, 3, 3, 1, 4, 2, 9, 0, 9, 7, 9, 1, 7, 0, 8, 2, 1, 8, 9, 9, 8, 1, 2
OFFSET
1,2
FORMULA
Equals (sqrt(Pi)/2) * erfi(1) = (sqrt(Pi)/(2*i)) * erf(i).
Equals Sum_{k>=0} 1 / ((2*k + 1)*k!) . - Ilya Gutkovskiy, Sep 18 2021
Equals A019704 * A099288. - R. J. Mathar, Sep 30 2021
EXAMPLE
1.462651745907181608804048586856988155...
MATHEMATICA
RealDigits[(Sqrt[Pi]/2) Erfi[1], 10, 91][[1]]
PROG
(PARI) intnum(x=0, 1, exp(x^2)) \\ Michel Marcus, Sep 18 2021
CROSSREFS
Cf. A347909 (inverse integrand), A007680.
Sequence in context: A029677 A045867 A236189 * A342875 A114403 A356763
KEYWORD
nonn,easy,cons
AUTHOR
Jianing Song, Sep 18 2021
STATUS
approved