Geometric Series

A geometric sequence is a sequence, such that each term is given by a multiple of q of the previous one. A geometric series consists out of the sum of all former values of a geometric sequence..

GeomSn(a1, q, n)

Arguments

a1

the first element of the sequence

q

the factor of the sequence

n

number of elements to include in the sum

Value

the sum as numeric value

Author

Andri Signorell <andri@signorell.net>

See also

sum

Examples

GeomSn(a1=3, q=2, n=5)
#> [1] 189

# calculates the sum of the first 5 elements of the sequence
(gseq <- 3 * (2^(0:5)))
#> [1]  3  6 12 24 48 96
sum(gseq)
#> [1] 189

GeomSn(a1=3, q=2, n=0:5)
#> [1]   3   9  21  45  93 189