A336686 Decimal expansion of Sum_{k>=0} 1/(k!)!.

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

Offset

1,1

Comments

The sum has 18 8's in a row within the first 23 decimal places.

1801/720 approximates this constant to 23 significant digits.

Links

Table of n, a(n) for n=1..104.

Example

2.5013888888888888888888905006...

Maple

evalf(sum(1/(k!)!, k=0..infinity), 112);  # Alois P. Heinz, Nov 20 2020

Mathematica

RealDigits[Sum[1/(k!)!, {k, 0, 4}], 10, 100][[1]] (* Amiram Eldar, Nov 21 2020 *)

Prog

(PARI) suminf(k=0, 1/(k!)!)

Crossrefs

Cf. A000197, A336810.

Sequence in context: A370541 A004598 A091086 * A371501 A385020 A384945

Adjacent sequences: A336683 A336684 A336685 * A336687 A336688 A336689

Keyword

nonn,cons

Author

Daniel Hoyt, Nov 20 2020

Status

approved