A099935 - OEIS

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A099935

Decimal expansion of Sum_{k>=0} (-1)^(k+1)*A000045(k)/k!.

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

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OFFSET

0,1

COMMENTS

This number is the coefficient of x in the reduction of e^(-x) by the substitution x^2->x+1; see A193026 and A193010.

LINKS

Table of n, a(n) for n=0..103.

FORMULA

Equals exp(-1/2)*(2/sqrt(5))*sinh(sqrt(5)/2).

Equals A098689 / e. - Amiram Eldar, Feb 07 2022

EXAMPLE

0.74102792152357735584178398667102441173255884250150...