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A359282
Decimal expansion of Integral_{x = 0..1} 1/x^(x^2) dx.
4
1, 1, 1, 9, 5, 4, 5, 1, 2, 0, 1, 3, 6, 1, 2, 7, 5, 9, 6, 6, 1, 2, 6, 7, 6, 2, 4, 7, 0, 2, 9, 8, 2, 7, 0, 3, 6, 4, 6, 0, 0, 4, 6, 9, 5, 7, 8, 7, 6, 4, 2, 7, 6, 2, 8, 9, 8, 6, 7, 4, 9, 5, 4, 6, 7, 5, 7, 0, 9, 4, 4, 0, 8, 3, 4, 4, 3, 2, 8, 3, 9, 8, 7, 5, 6, 8, 6, 2, 6, 4, 5, 3, 8, 2, 0, 1, 0, 7, 7, 3, 0, 0, 5, 9, 7, 9, 9, 4
OFFSET
1,4
FORMULA
Equals Sum_{n >= 1} 1/(2*n - 1)^n.
More generally, Integral_{x = 0..1} 1/x^(t*x^2) dx = Sum_{n >= 1} t^(n-1)/(2*n - 1)^n. See A253299 (case t = -1).
EXAMPLE
1.119545120136127596612676247029827036460046957876427628986749 ...
MAPLE
evalf(Sum(1/(2*n-1)^n, n = 1..infinity), 120);
MATHEMATICA
NIntegrate[x^(-x^2), {x, 0, 1}, WorkingPrecision -> 103] // RealDigits // First
PROG
(PARI) intnum(x = 0, 1, x^(-x^2))
KEYWORD
nonn,cons,easy
AUTHOR
Peter Bala, Dec 24 2022
STATUS
approved