A248678 Decimal expansion of r = sum_{n >= 0} floor(2n/3)!/n!.

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

Offset

1,1

Links

Clark Kimberling, Table of n, a(n) for n = 1..1000

Formula

r = sum_{n >= 0} (9 n^2 + 14 n + 5) (2 n)!/(3 n + 2)!.

Example

r = 3.0101448539910523219116461487677327...

Maple

evalf(sum(floor(2n/3)!/n!, n=0..infinity), 120); # Vaclav Kotesovec, Oct 17 2014

Mathematica

x = N[Sum[Floor[2 n/3]!/n!, {n, 0, 200}], 120]
RealDigits[x][[1]]  (* A248678 *)

Crossrefs

Cf. A248675, A248676, A248677.

Sequence in context: A354824 A183700 A275478 * A325268 A232630 A331569

Adjacent sequences: A248675 A248676 A248677 * A248679 A248680 A248681

Keyword

nonn,easy,cons

Author

Clark Kimberling, Oct 11 2014

Status

approved