Zseq (version 0.1.1)

Factorial.Double: Double Factorial numbers

Description

Under OEIS A000165 and A001147, a Double Factorial is the factorial of numbers with same parity. For example, if \(n=5\), then \(n!!=5*3*1\).

Usage

Factorial.Double(n, Rmpfr = TRUE, PrecisionBits = 496, odd = TRUE)

Arguments

n

the number of first n entries from the sequence.

Rmpfr

a logical; TRUE to use large number representation, FALSE otherwise.

PrecisionBits

a positive integer for precision bits larger than 2.

odd

a logical; TRUE for double factorial of odd numbers, FALSE for even numbers.

Value

a vector of length n containing first entries from the sequence.

See Also

Factorial

Examples

# NOT RUN {
## generate first 10 Factorials
first10 = Factorial(10)

## print without trailing 0's.
print(first10, drop0trailing = TRUE)

# }